Science
10
Your Inner Fish
Neil Shubin
June
2009
The Link
Colin Tudge
July 2009
Physics for Future Presidents Richard A. Muller July 2009
1491
Charles
C. Mann Aug 2009
Audio Book
liars, lovers, and heroes
Steven
R. Quartz & Terrence J. Sejnowski Oct 2009
Your
Inner Fish
Neil
Shubin
June 2009
Subtitle:
A Journey into the 3.5 Billion-Year History of the Human Body
Preface Because of faculty
departure, Dr. Shubin, a paleontologist, ended up teaching human
anatomy in the Medical School at the University of Chicago. It
turns out that this is a pretty good way to teach the class. The
pathways of nerves in the head are similar and much more obvious in
sharks, the best way to visualize how limbs form is to study the bones
of fish fins. And then after only teaching the course several
times he and colleagues discovered the fossil of a fish like animal
that was one of the first to walk on land approximately 375 mya.
C1 Finding Your Inner Fish
To find fossils from a particular period of time you need to find
rocks of the right age, rocks that are of the right type to preserve
fossils, and rocks that are exposed at the surface. As a new
paleontologist working in Philadelphia he and a partner were interested
in studying limb development. They thought that there might be
fossil evidence of the time when fish first came onto land in fossils
of between 360 and 380 million years old. They found a map in a
geology textbook that showed exposed sedimentary rock of that age in
three areas of North America, eastern Pennsylvania, the east coast of
Greenland, and several islands in the Canadian Arctic. They went
to the closest first, the road cuts in Pennsylvania. They
did find one helpful fossil but Pennsylvania has a lot of trees,
cities, roads, etc., not exposed rocks. Another person had
done considerable work in Greenland so that left the Canadian Arctic.
The author and two colleagues received a grant and set off for
Ellesmere Island at 80 degrees North. For six years and four
expeditions they searched for appropriately aged fossils. Then in
July 2004 they found several fossils including the best one of their
primary find. It was fish-like with scales and fins but it also
had a flat head and a neck. It also had bones that correspond to
the upper arm, the forearm, and parts of a wrist. All of the
joints were there. This was a fish with a shoulder, elbow, and
wrist joints all inside a fin with webbing. The fossils were
found in the Nunavut Territory of the Arctic and the Inuit living in
the area had given their permission to dig for fossils. The
paleontologists asked the Nunavut Council of Elders to help with the
naming and the name that they came up with was Tiktaalik which means "large freshwater fish."
After he got home his son's preschool teacher asked him to bring a cast of the Tiktaalik
fossil into his son's class. After he described his exploration
and asked for comments on the fossil. Some of the four- or
five-year-olds thought it was like a crocodile or an alligator.
Some thought it was more like a fish but then one shouted, "Maybe
it is both." Obviously they had found the right fossil.
C2 Getting a Grip The
first time the author did a human dissection he handled the internal
organs really well, he had more problems with the hand. The bones
of many of the upper limbs of most animals are very similar. His
description is interesting; one big bone articulating with two smaller
bones, which attach to "a series of small blobs", which connect to
fingers or toes. The differences lie in the shapes and sized of
the bones and the numbers of blobs, fingers, and toes.
This pattern holds for almost all species of animals from fish to
mammals. This feature first arrived about 380 mya. The
first fishes with this structure probably had relatively stiff fins.
The fossil that the author found, Tiktaalik,
was slightly younger, 375 my, and had a true wrist which could bend.
Interesting point about the ecology of the time, most of the fish
species found were predators. Some were up to 16 feet long, twice
the size of the largest Tiktaalik and the most common fish that they have found was about 7 feet long and had teeth the size of rail-road spikes. Tiktaalik had good reason to walk out of the water. Before Tiktaalik the wrist and arm bones did not exist, after Tiktaalik
the wrist and arm bones exist in almost every species including humans.
The first true fingers and toes is first seen in a 365 my old
amphibian and the first full compliment of wrist and ankle bones really
similar to the human hand or foot is found in reptiles more than 250 my
old. The importance of these bones and their shapes lies in their
abilities to move. As the shapes of the bones and sockets which
form the joints have evolved the range of movement has changed allowing
each successive animal more opportunities.
C3 Handy Genes At the same time that the author, Shubin, was digging up Tiktaalik
in northern Canada a researcher in Shubin's lab in Chicago was doing
genetic experiments on the embryos of sharks and skates. These
experiments had started out in the 1950's and 1960's on chickens,
expanded to fruit flies in the 1990's where they discovered a gene
which they called hedgehog as a mutation of it produced little bristles which reminded the researchers of a little hedgehog. When it was discovered in chickens it was given the name Sonic Hedgehog
after the video game. It was subsequently discovered in every
other animal they tested including humans. This gene seems to
control the development of upper arms, forearms, wrists, and digits in
all animals that have limbs. The researcher in Chicago, Randy
Dahn was testing to see if it would work in animals, sharks and skates,
that had diverged from the line leading to mammals more than 400 mya.
In short, it did.
C4 Teeth Everywhere
The author's first successes occurred as a graduate student
assisting professors hunting fossils. He went out with
professional fossil hunters and preparers and learned how to do field
work from them. It was mainly an exercise in learning how to look
for fossils and the little clues that distinguish a fossil from other
rocks. Teeth were the first fossils that he learned how to find.
This is not surprising, teeth are the hardest bones in a skeleton
and are therefore the most commonly preserved.
Small mammals were the earliest animals to show a feature of jaws and
teeth that set mammals off from crocodiles and lizards, that is
matching patterns of upper and lower teeth. About 200 mya small
mammal like creatures known as tritheledonts started developing
matching patterns of teeth which could shear food off like scissors.
By about 150 mya many small mammals have developed more complex
types of teeth which could stab, cut, and mash food.
Teeth and all bones contained a crystal molecule called hydroxyapatite,
the outer layer of teeth, the enamel, has more hydroxyapatite than any
other structure. Some of the earliest common fossils are called
conodonts. They were found in rocks between 500 my old and 250 my
old. It was much later discovered that these independent fossils
were in actuality the teeth of soft-bodied jawless fish. Hard
structures, teeth, developed first and then additional structures built
is a very similar manner, bones, developed and animals that used these
structures became very successful as they could swim, bite, chew, and
swallow food quite efficiently.
Another interesting thing about teeth is that they, as well as hair,
feathers, and breasts develop in a similar manner. In all of
these two layers of tissue in the skin interact with each other to make
new structures. These two layers come together, fold, and secrete
proteins. The genetic switches that are active in this process
are very similar in all four organs.
The goal of these four chapters is to demonstrate that similar body
parts and genetics can be traced widely through life on earth. He
uses four different types of examples to demonstrate that no matter
which parts of humans and other animals you pick, they all can be
related to almost all other animals on our planet.
C5 Getting Ahead This
chapter discusses the anatomy of the head. As an example he
describes the remodeling of his lab at the University of Chicago.
It had been built in 1896 and he was assign the area in 2001.
Over the years it had been upgraded many times but to convert it
to a lab it needed a major renovation. When the walls were opened
up the evidence of earlier remodels was evident. Plumbing,
electricity, and ducts went everywhere - no one would have designed a
laboratory like this from scratch but it worked and it was cheaper to
just make modifications and the new purposes could be achieved at
minimal cost. He shows how parts of our anatomy are similar to
fossil worms over 530 my old and parts or our embryos are very similar
to shark embryos. This can make an understanding of our anatomy,
especially the facial nerves, very difficult for beginning anatomy
students. It is much clearer when you understand the evolution of
our ancestors beginning with primitive worms 530 mya through sharks and
other ancestors.
C6 The Best-Laid (Body) Plans
How animals develop. The scientific study of embryology
pretty much began with Karl Ernst von Baer in the late 1820's. He
discovered that all organs in a chicken developed from one of three
layers of tissue in a developing embryo. This was later
generalized to all animals. The next major developments started
in the lab of Hans Spemann in 1903 and especially with a graduate
student of his, Hilde Mangold. They discovered that a tiny patch
of tissue seemed to control all growth is an embryo and it became known
as the Organizer. Unfortunately for Spemann (Mangold died very
early) and other researchers the technology was not available for any
more basic discoveries until the 1980's and 1990's with the discovery
of controller genes. Some of these controller genes are the
homeobox (better know as Hox genes), Noggin, and BMP-4.
These and others extremely similar are found in animals like
humans, fruit flies, and sea anemones. The closer any two species
of animals are related the more similar the genes are. For
example, the sea anemone only has two major body parts, the front end
and the back end, and it therefore has no genes for controlling
development of a central region which humans have.
C7 Adventures in Bodybuilding
A "body" is more than just a simple collection of cells. A
mat of bacteria or a collection of skin cells is very different from a
group of cells forming an individual. As one example you can
remove a piece of a bacteriological mat and have a big mat and a small
mat. However if you remove a piece of a heart or a brain you will
likely kill an animal. In a body the components work together to
make a greater whole. There were free living cells around for
perhaps 3.5 billion of the 4.5 billion years that the earth has existed
but bodies have existed for only the last billion years or so.
One of their main features is that the cells in a body have
mechanisms to hold them onto other cells. Bodies are composed of
several different types of cells. These types of cells serve
different functions. Cells also communicate with each other,
typically by secreting and sensing different chemicals. Cells
arrange themselves into bodies by means of such communication.
For example you can break sponges into their component cells by
means of sieves. If you put them back together they will slowly
reform into a complete sponge.
Some single cell species, for example the choanoflagellates, contain
many of the same genes and presumably the same capability to form into
bodies that multicellular animals do. Some recent thinking on
this is that these capabilities arose perhaps billions of years before
bodies did but that the earth's ecosystem did not contain enough free
energy to make bodies useful. For example, collagen, a very
important chemical in keeping body cells together, requires much more
energy to synthesize than do many other chemicals. During the
first 3.5 billion years there was very little free oxygen on earth.
Then about a billion years ago the level of oxygen increased
greatly. Over a relatively short period of time the amount of
chemical energy available increased greatly. More complex bodies
became much more profitable. An experiment along this line was
recently performed. A normally single celled alga was raised in a
lab for over a thousand generations. It remained as single cells,
never clumping into larger groups. Then a predator species was
introduced that could ingest single algae cells. In less than 200
generations the alga evolved into a species that clumped into groups of
hundreds of cells. Over time the groups reduced in size until
they arrived at groups of about 8 algae cells. Presumably this
resulted in groups that were too big to eat but each algae cell could
pick up enough light to survive quite well. When the predator
species was removed the groups stayed at about 8 cells per group.
There was real advantage to the alga to reduce the size of the
groups
C8 Making Scents
Recipe to separate DNA: Take an amount of tissue from some
source, add some salt and water and put into blender - mix well.
Then add some dish soap - this breaks up the cell membranes that
were not broken by the blender. Add some meat tenderizer - this
breaks up some of the proteins that attach to DNA. Add some
rubbing alcohol to the mix - this will separate the mixture into a
soapy mush on the bottom and clear alcohol on the top. DNA has an
attraction to the alcohol and it will move into it. If you have
done everything right and it all worked you should have a gloopy white
ball in the alcohol. The gloop is the DNA that was contained
within the tissue. The rest is probably beyond kitchen-table
biochemistry.
A discussion of the sense of smell. A sense of smell is important
to most species. It would seem that there is a genetic basis for
each different smell sensor so many genes are involved in smell.
Two researchers, Linda Buck and Richard Axel, discovered in 1991
a large family of genes that give us our sense of smell. They
discovered that 3 percent of our entire genome is devoted to genes for
detecting different odors. In 2004 they received the Nobel Prize
for their work. Since the original discovery considerable work
has been done on the genetics of smell. A number of interesting
facts have turned up. Some primitive fish have odor genes that
are neither optimized for smelling chemicals in air nor water - they
split off the evolutionary tree before the genes diverged.
Mammals like whales and dolphins have the normal mammal
complement of odor genes but none of them are active as their nasal
passages are now used for other purposes. Primates including
humans that have developed color vision and whose life emphasizes
vision have lost many of their genes which were devoted to smell.
C9 Vision One of the
authors most memorable discoveries was made in the back room of a
mineral shop in China. He and a Chinese colleague were trying to
buy a 160 myo salamander, after several hours of negotiating in Chinese
(which he does not speak) he purchased the fossil. It turned out
to be a beautifully preserved larval salamander and for the only time
in his career he saw the eye of an ancient fossil animal.
Although there are many anatomically different eyes, chemically they
are all very similar. They all contain a chemical that absorbs
light and breaks apart. One part is derived from vitamin A and
the other is a protein known as an opsin. When the opsin is
broken off it initiates a chain of chemical reactions that results in a
neuron sending a signal back to our brain. Opsins use a
specialized type of conductor that takes a series of bends and loops as
it travels from the outside to the inside of the cell. This same
type of twisted conductor path is seen in parts of certain molecules in
bacteria. The basis of all vision was developed in bacteria
hundreds of millions of years ago.
We have three different types of light receptors however most animals
only have two types. Most animals can only see two primary colors
whereas we and the other old world monkeys can see three primary
colors. Since we split off from the other primates about 55
million years ago and the evidence suggests that flowering plants and
multicolored plants arose about that time it would seem that the
mutation that added an additional color to our vision was a significant
benefit to our ancestors.
Studies of the anatomy, physiology, and genetics of the very primitive
worm, Polychaetes, fruit flies, bacteria, and mice have shown that
"eyes" or at least vision has been around for a very long time,
different species have put together the parts in very different manners
but we and the old world monkeys are the beneficiaries of the best
color vision.
C10 Ears The ear, a
sort of confusing structure. The outermost part, the pinna, that
gathers and focuses sound is found only in mammals. It leads into
a tube that ends in an eardrum. The middle ear is strictly
mechanical and consists of three bones. The first two, the
malleus and the incus, are highly evolved bones that started as a part
of the jawbone in early reptiles. The malleus picks up vibrations
from the eardrum and passes these to the incus. The stapes
evolved from a bone at the rear of the upper jaw in early sharks.
The stapes picks up the vibrations from the incus and passes them
to an opening into the inner ear. The advantage of this
arrangement is that it allows mammals to hear higher-frequency sounds
than animals with a single middle ear bone. Hearing in water is
different from hearing in air and when our ancestors (around the time
of Tiktaalik) came out onto dry land a change would have given them an advantage.
The inner ear contains three separate but similar organs. They
sense balance, acceleration, and hearing. They are all based on
the movement of fluid that moves and disturbs little hairs on nerve
cells. The precursors were formed around 500 mya and the fossils
are not detailed enough to be sure exactly how it happened but the
lateral line nerve cells in fish work in the same way. The genes
related to hearing and vision, Pax 2 and Pax 6, seem to control most of
the development of ears and eyes and a single gene related to Pax 6 is
found in the box jellyfish of Australia. The hypothesis is that
both eyes and ears arose from genes similar to those found in this
stinging jellyfish.
C11 The Meaning of It All
Some of the most heated arguments in biology concern taxonomy.
This may seem ridiculous but it stems from one of the most basic
facts of biology, all animals have parents and just who are these
parents? If you can follow this to its logical conclusion you
could tell who or what is related to whom and place every living thing
on their appropriate spot in the family tree. Unfortunately this
is a little more difficult than it sounds. Another point here is
that evolution very seldom "invents" something new, the most common
process is to use an old part to perform a new application.
Unfortunately this sometimes leads into evolutionary dead ends or
more realistically very complex "work-arounds" that accomplish a task
but leaves a disaster prone-solution. He offers a number of
anatomically "stupid" solutions that cause us many problems. Some
of these are knees, arteries, nerves, veins, backbones, active vs.
sedentary life, need to store fat, hernias, mitochondrial diseases,
etc. There are many problems with talking; choking, sleep apnea,
hiccups
There is a notes, references, and further reading section arranged by chapter of 12 pages and an 11 page index.
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The Link
Colin
Tudge
July 2009
Subtitle: Uncovering Our Earliest Ancestor
C1 Discovering Ida
Ida is the fossilized remains of a small primate. Ida was
born beside a small lake in what is now Germany 47 million years ago.
When Ida was born, the lake, along with most of the rest of
Germany, was a tropical area, approximately where Sicily is today. The
area had been volcanic and in fact the lake was formed when a blob of
molten magma rose through the earth and encountered groundwater.
The resulting steam explosion created a hole about a mile wide
and more than 800 feet deep. When the hole filled with water it
created a lake which is known as a marr lake.
Since the lake was very still and deep and in a tropical
environment, surface algae grew on top and when it died it sank to the
bottom. This process uses up all of the oxygen as it decays so
very little additional decay occurs. The algae becomes muck, then
mud, and then rock. The rock contained the oil from the algae and
so it turned into oil shale. The first use of the Messel pit was
to dig up the oil rich rock to process it for petroleum.
The first major fossil find was a part of a crocodile on Dec 30, 1875.
Fossil digging co-existed with mining until 1971. Sometime
in 1982 a fossil hunter found a fossil of an "exotic monkey", took it
home and preserved it.
Ida is about a year old primate. She was probably feeding or
getting a drink when a large bubble of carbon dioxide (which was given
off by the residual volcanism below the lake) surfaced, killing all
animals on or close to the lake. She fell into the lake and sank
to the bottom where she was entombed in the muck and mud. Very
little decay occurred because of the lack of oxygen.
The fossil hunter who found Ida was getting older and wanted to sell
her. He hired a dealer who privately contacted Jorn Hurum (at the
University of Oslo) during the Hamburg Fossil Fair. It was a
stressful time for Horum because of the price asked ($1,000,000 US),
the need for secrecy, limited time, and the necessity of assuring that the fossil was legal to sell.
C2 Ida's Story Begins
A brief look at primate archeology and Donald Johanson's
discovery of Lucy in 1974. A more detailed look at Horum's
picking a team to assist in the analysis of Ida, details of purchasing
and verifying the authenticity of the fossil. Considerable work
was done at a museum in Darmstadt as they have more expertise in Messel
fossils than anyone else. The fossil of Ida was moved to Oslo in
September 2007 where the team continued work on the fossil and
beginning on the scientific papers.
C3 Ida's Eocene World
A description of the earth from roughly the end of the dinosaurs
(65 mya) until the end of the Eocene (34 mya). The Eocene (56 mya
- 34 mya) started out with 5 my of very warm climates - palm trees in
Alaska and Siberia and no polar ice caps. It is believed that it
was warm enough to melt the clathrates (methane-ice) which gave the
climate a big boost warmer several times around 56 mya. About 40
mya India, which had been drifting north, made contact with the south
coast of Eurasia. It kept on moving which raised the Himalayas
and the Tibetan Plateau. This changed the wind patterns and
carries bicarbonates into the ocean which removes carbon dioxide from
the air. This slow cooling process has existed ever since.
Flora during Stone Rose - conifers, cycads, ferns, and flowering plants. Fauna - Uintatherium, Andrewsarchus, multituberculates, Eocene whale (Aeuglodon or Basilosaurus), (fish, snakes, modern frogs, butterflies, honeybees, and birds look much as they do today. Large birds of prey, Diatryma, ancient horses, Tapirs (Hallensia mathesi), bats, etc. Spinless hedgehog (Macrocranion trpaiodon), turtle (Allaeochelys Crassesculptata), fish (Amphicarca multiformis), bat (Paleochiropteryx tupaiodon), crocodile (Diplocynodon darwini), insects (walking leaf), ant (Formicium), fish: gar( Atractosteus strausi), bowfin (Cyclurus kehleri), eel (Anguilla), frog (Pelobates), crocodiles (Baryphracta deponiae and Pristichampsus), birds (Messel rail => Messelornis cristata), and (Diatrymal / Gastornis) and (Palaeptos weigelti), (Juncitarsus merkeli), Messelirrisor & Primozydodactylus, mammals (Boxolestes, Leptictidium, Kopidodon, Heterohyus, creodonts (Lesmesodon), marsupials (Paradectes), anteater (Eurotomandua), carnivores (Paroodectes), squirrel (Ailuravus macrurus), other rodents (Hartenbergeromys parvus, Masillamys beegeri, Eogliravus), Philidocercus, Macrocranion tupaiodon, tapirs (Hyrachus), horses (Propalaeotherium, Hallensia, Eurohipus messelensis), primates (Europolemur koenigswaldi & E. Kelleri). Early Archaics and Prosimians: Adipus, Purgatorius, Plesiadapis, Teilhardinia, Cantius, Aegyptopithecus, and Proconsul, Eosimias, Amphipithecus, Siamopithecus, and
Pondaungia, Apidium, Propliopithecus, Pilopithecus, Aegyptopithecus
zeuxis, Oligopithecus savagei, Catopithecus, Proconsul, Dryopithecus,
Sivapithecus, Ramapithecus, Kenyapithecus, Gigantopithecus blacki,
Nakalipithecus nakayamai, Ouranopithecus, Australopoithecus africanus,
Australopithecus afarensis (Lucy),
Paranthropus (Zinjanthropus), Ardipithecus ramidus, Orrorin,
Sahelanthropus, Homo habilis, Australopithecus habilis, Homo
rudolfensis, Homo eretus, Homo florensiensis, Homo heidelbergensis, and Homo neanderthalensis and Altiatlasuis.
C4 The Messel Pit This chapter goes into much greater detail about the geology and ecology of the Messel pit and Maar.
C5 How Primates Became
Basic biology and sociology of primates. Primates come in
many sizes, the pygmy mouse lemur is about 2½ inches long and
weighs about 1 ounce and an alpha male gorilla may weight more than 330
lbs. They live all over the world (the poles require technology),
in trees and not.
Many groups or animals have a single distinguishing feature but
primates do not. Primates have a number of characteristics but
not all have all of them and some animals who have one or more
characteristics are not primates. Some of these are fingernails,
collarbones, large eyes that can see in color, bony eye socket,
opposable thumb and/or big toe, two breasts, a pendulous penis,
testicles in a scrotum, three types of teeth, and extremely mobile
arms. The author describes the taxonomy from a primate point of
view, clades and how they are broken up in terms of grades (primitive
=> resembling their ancestor vs. derived => changed from
ancestral forms).
Avoiding some of the taxonomy terminology the primates are broken into
two groups, the prosimians and the simians or anthropoids. The
prosimians are divided into the lemurs, lorises, pottos, bush babies,
and tarsiers. The anthropoids are broken into two major groups,
the New World monkeys and the Old World primates which include monkeys
(which have tails) and the apes (which do not have tails).
Primates generally have brains that are proportionally larger than most
other animals and since brains consume a great deal of energy most eat
a lot of high energy foods like fruit or other animals which contain
large amounts of protein and fat. Large brains are useful for two
reasons, the first is that they are needed to manipulate complex hands
and the second is that primate groups are based on socializing within
the group. A large portion of the chapter is devoted to the various types of primate societies.
C6 Primate Evolution
Just normal evolution but pulling most of the examples from
primates and their earlier relatives. The first issue is that
fossils of any sort are very rare and the second is that the fossils
that we would like to find the most, those from the first few
generations of a new species, and these animals themselves were very
rare so there is a double strike against them.
The first mammals originated about the same time as the first
dinosaurs, about 200 mya. Unfortunately for the mammals, they
were quite small, possibly about the same size as shrews. If any
showed signs of evolving into larger animals they just became more
attractive morsels of meat for existing dinosaurs or other predators.
Birds first evolved around 140 mya. It seems that mammals
diverged into the placentals and the marsupials diverged from each
other about 130 mya. The first primates probably evolved around
80 to 90 mya, they probably resembled modern tree shrews. When
the dinosaurs died off, 65 mya, all mammals were free to expand into
ecological niches that had been dominated by dinosaurs up until then.
It is quite likely that primates originated in the Northern
Hemisphere, either in North America or in Europe. Unfortunately
there are very few fossils of any sort from Africa of this age.
The archaic primates were very successful, spreading all over the
world where fossils are found. However around 50 mya they were
starting to decline. They were being out-competed by the rodents
and by their descendants, the prosimians.
The prosimians were also very widespread, being found in both America
and in Europe. Somewhere around 40 mya fossil primates disappear
from everywhere but Africa until about 20 mya the first New World
monkeys appear in South America. No one knows how they got there
as there is no fossil record of intermediate forms.
C7 From the Eocene to Us
The Eocene was very warm and wet. Most of the land masses
were connected although from time to time there were breaks in the
unity. However several areas were completely cut off until fairly
recently, these were South America, Australia, India, and Antarctica.
About 34 mya the world started to become much dryer and cooler.
Grasses became much more widespread. The aquatic fern
Azolla was widespread in the Arctic Ocean at the time and as
individuals died huge amounts of carbon were sequestered on the bottom
of the ocean. As explained earlier India crashed into Asia and
the Himalayas
and the Tibetan Plateau were forced upward which caused vast amounts of
carbonated to be sequestered on the bottom of the ocean. Earth's
orbit changes cause warming and cooling at about 100,000 year intervals
but these probably have no effect on longer term temperature changes.
The remainder of the chapter discusses the many varieties of
primates that have occurred since Ida that may have played a roll in
human evolution. Many of these are listed in the second paragraph
of Chapter 3, Ida's Eocene World.
C8 Who and What Is Ida?
The first question is, "Why is Ida important?" She is very
old (47 my) and she is very well preserved, probably better than any
other set of remains up to the Ice Man or the Egyptian mummys.
She also comes from a time when our own group, the anthropoids,
were in the process of splitting off from the other groups of primates.
There are four main proposals as to how the different groups
within the primates split off from each other. Ida will be able
to answer some of these questions.
The fossil is so clear and detailed that we can tell what she had for
her last meal (fruit), that she had very muscular legs, and that she
was female. We have a pretty good idea of how and why she died.
The author suggests that we don't call her Grandmother as she was
too young to have offspring and many think that those in our direct
line must have been living in Africa at the time but perhaps we could
call her Aunt.
C9 Revealing Ida to the World
For a fossil to form the creature must die in specific
conditions. It must be covered soon after death so as to not be
eaten or decomposing due to the presence of bacteria. The final
resting place must remain geologically stable for millions of years.
Then it must be found, properly extracted, and compared to the
rest of the record. The author then goes on to repeat briefly
what her life was like and the anatomical characteristics place her in
the primates and how she is similar to and different from specific
lineages.
Most of the rest of the chapter discusses the considerations in
announcing a find of this magnitude. How it should be presented
to make the most of the resultant publicity but retaining scientific
authenticity. Several other recent finds are discussed to present
the pitfalls and opportunities that occur.
The book contains a 12 page index.
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Physics for Future Presidents Richard A. Muller July 2009
Subtitle: The Science Behind the Headlines
Introduction As President
you don't have time to call in a series of experts when the CIA or
someone tells you that terrorists have planted a dirty bomb in midtown
Manhattan. You have to take an appropriate action and quickly.
Your available advisers may have their own agendas and you must
carefully evaluate their recommendations. You have to know the
basic physics behind the situation. As Mark Twain is commonly
quoted as saying, "The trouble with most folks isn't their ignorance. It's knowin' so many things that ain't so." Of course Twain didn't actually say this, Josh Billings did.
In the book he covers terrorism, energy, nuclear considerations, space,
and climate change. He doesn't try to cover the science in
detail, he only covers the basic principles and tries to show how these
effect the possible problems in the above areas.
I TERRORISM
C1 Nine-Eleven The
planes hitting the World Trade Center in 2001 released about 1.8 k-tons
of energy, considerably above the North Korean nuke test in 2006.
Where did it come from? The kinetic energy of two airplanes
weighing 131 tons traveling at 600 mph is only about the equivalent of
1 ton of TNT. The rest of the energy came from the 60 tons of
fuel in each airplane burning. Each ton of burning gasoline
releases the same energy as 15 tons of exploding TNT. The towers
were destroyed by burning gasoline weakening the steel in the buildings
and they "melted".
Inspecting Passengers:
Metal detectors and X-rays can be used but they are not very
precise. However without full strip searches and item by item
searches of luggage, decisions have to be made about sensitivity.
The 9/11 terrorists were successful not because of their
technology, they were successful because of our policies. Taking Control:
Previous airline hijackers did not harm the pilots or passengers,
therefore there was no defense against people taking over airplanes.
Flying and Navigating the Airplane:
Flying an airplane is easy, if you don't have to take-off, land,
or navigate. The hijackers just had to fly down the Hudson River
and then aim for the biggest building. Impact: Again, the impact or any explosion did not seriously damage the towers, it was the fire.
C2 Terrorist Nukes It
is possible to build a small nuclear weapon, the US did in 1962, it is
just incredibly difficult. Also the blast of such weapons is not
big enough to do serious damage to our society. The original
design for such weapons was to use on battlefields but not do too much
damage. To do serious damage a large number would have to be
used. Big Nukes:
The nuclear bombs carried in nuclear missiles or B-52's can do
very serious damage but they are all two-stage weapons and are super
incredibly difficult to build and fire successfully.
The Terrorist Dirty Bomb:
Radioactive material can be very dangerous for a few people in a
limited area. However it is not feasible to place enough
radioactive material over a wide area so as to be generally dangerous.
It takes too much difficult to acquire material. Even then
the likely result is a general increase in the amount of cancer over
many years. Not a good terrorist weapon. The most danger is
political where the bomb would be a weapon of mass disruption instead
of mass destruction.
Rogue Nukes: The greatest danger is that terrorists will acquire an existing nuclear weapon from one of the countries that has them. Uranium Bombs:
Designing a U-235 uranium bomb is easy, it is difficult to
separate U-235 from U-238. The best way to detect them is by
looking for supplies needed to separate uranium isotopes.
Plutonium Bombs:
Plutonium is easy to get as it is a byproduct of nuclear power
plants. However plutonium bombs are very difficult to build.
They need to be built of very carefully machined plutonium pieces
that need to be very accurately exploded together. A lengthy
testing program would probably be necessary.
C3 The Next Terrorist Attack
Probably it won't be a commercial flight as the crew and ground
support staff are very sensitive to this possibility. Most of the
bombers involved in 9/11 should have been caught on the ground if
surveillance and policing had been doing their jobs. A crop
duster airplane would be a very good alternative for carrying gasoline
however these are difficult for personnel reasons. (comment:
a fire-fighting airdrop tanker would be a great alternative).
Another alternative is putting bombs on airplanes. Our
current security techniques pretty much rule out remotely planted
devices or big devices but small carry-on suicide devices would be very
hard to detect. Our best alternative is proactive and intelligent
screening of passengers. We have not had a successful attack on
airlines since 9/11.
C4 Biological Terrorism
Just a week after 9/11 there was a second terrorist attack, it
was anthrax spores. It was (successful / unsuccessful)?
Only 5 people were killed. If the goal was millions it was
unsuccessful, if the goal was to scare people it was successful.
The problem with biologicals is the method of spreading the
active agent to a susceptible population. It is very difficult to
disperse the active agent so that every targeted person gets enough of
a dose to cause the disease without wasting most of the agent when it
falls on the ground or is diluted to far or destroyed by other means -
heat, ultraviolet radiation, etc. Biological agents are still
likely to be the most dangerous terrorism agents.
Presidential Summary:
Maintain vigilant against the possibility of terrorist attacks
even though there has not been one in many years, the informed
observations of American citizens is probably your best weapon.
The current precautions are doing the job, keep them. The
dangers of smuggling a nuclear weapon in as cargo is real but the
likelihood is quite small, for most nuclear weapons the explosive
device is too small to do major damage to an area. Dirty bombs
are generally a fear producing device, they would be an irritant not a
clear danger. Gasoline bomb attacks are much more likely and here
the best weapon of prevention is an alert flying community.
Multiple smaller attacks on airliner are possible but coordination is
very difficult. Biological terrorism is probably the greatest
risk.
II ENERGY
Energy is important because it is linked to national wealth.
The last two wars were fought because of energy supplies.
Energy and global warming seem to be our most serious problems.
C5 Key Energy Surprises
Of all the areas of physics, energy has the most things that
people know that just ain't so. He has a list of surprising
facts, some are: gasoline has 15 times the energy as TNT by weight,
coal is twenty times cheaper than gasoline, liquid hydrogen has 4.5
times less energy per gallon than gasoline. Why We Love Oil: Gasoline
carries huge amounts of energy and it is very convenient. Most
other fuels have serious problems but they can be used is specific
conditions. Power:
People confuse energy with power, power is the rate of energy
used. Gasoline has more energy than TNT but TNT can release it
much faster than gasoline burning in air. Some basic
equivalences. 1 horsepower = 1 kilowatt = the amount of solar
energy falling on 1 square yard at noon, 1 kWh =~ 1000 food
calories. Tables of where energy is used and where it comes from
are presented. Also there is a table of costs per kilowatt-hour
for several energy sources.
C6 Solar Power Solar
power is often misunderstood. He tells the story of an
interaction with a former student with a fusion power expert. The
student stumped him when she said that a square kilometer of sunlight
has an energy potential of gigawatt nuclear power plant. A short
table of overhead sunlight potential; 100 watts per sq. ft., 1 kw or 1
hp per sq. yard or meter, 1 gigawatt per sq. km., 3 gigawatts per sq.
mile. A solar powered auto is not practical, a solar powered
house could be - the problem is mainly the efficiency, cost, and life
span of solar cells. Solar power plants are much closer to
breaking even economically. A solar powered airplane, the Helios,
has flown to a height of 96,863 feet and can carry a payload of about
100 lbs at a speed of about 20 mph. Not a great passenger
airliner but a remarkably efficient platform for a telescope, camera,
and radio.
C7 The End of Oil The
famous Hubbert oil curve showing the past and predicted production of
oil including peak oil. When an oil well is first drilled between
20% to 30% comes up easily. When water or carbon dioxide is
pumped down the well then an additional 30% to 60% can be pushed out.
The rest is more difficult. Oil can be produced using coal
using the Fishcr-Tropsch process but it is expensive so the price of
oil must be more than $50 per barrel to make a profit currently.
Since about 1970 the price of oil has been primarily determined
by global politics, especially Middle East vs. Western Nations.
Presidential Summary:
There are a lot of "untrue facts" out there. We are not
running out of fossil fuels but we are running low on oil. There
are other possibilities but they need more research and development.
There is only one absolutely guaranteed approach that will always
work, conservation.
III NUKES
We are all radioactive. Biofuels and whiskey is
radioactive, only fossil fuels are not radioactive. There is
probably more misinformation about radioactivity than any other topic
in physics.
C8 Radioactivity and Death Radioactivity
is the explosion of the nucleus of an atom and a few particles with
high energy are released. The energy released is about a million
times as much energy per atom than is released in a TNT explosion per
atom. Fission, when the nucleus explodes into two relatively equal sized particles releases about 20 times more energy. Radiation
is the name for the fragments that fly out when the nucleus explodes.
The radiation fragments are like the shrapnel from a grenade,
they are what cause the damage. They tear molecules apart in the
cells of the body. Radiation is measured in rem. You probably wouldn't notice the damage caused by 100 rem. At 200 rem you would notice radiation poisoning,
your hair will probably fall out, you will feel nauseated and listless.
At 300 rem about half of those exposed will die, this is the LD50
level. At 1000 rem you would be incapacitated within a few hours
and even with the best medical treatment almost everyone would die.
Any dose of less than 100 rem is almost never noticed with one
exception. Cancer. Even at very low levels radiation may
damage cell DNA and a cancer may develop, typically much later.
Radiation and Cancer:
There is nothing sure about radiation and cancer. It is all
probabilities. There are many other causes of cancer. It is
very difficult or impossible to separate out exact causality. It
is estimated that 20% of us die of cancer from unknown causes so if the
normal rate is 20% and we get a dose of radiation which is expected to
result in a 4% death by cancer, then our true risk of cancer is 24%.
Figures are presented that of the 100,000 survivors of Hiroshima
and Nagasaki who were exposed to radiation that we would expect 800 to
die of cancer. Of the 20,000 who will die of cancer from other
unknown causes, how do we know which of the 20,800 who die of unknown
causes and radiation exposure were caused by radiation exposure?
The Chernobyl Nuclear Reactor Disaster:
In 1986 a nuclear reactor near Chernobyl in Ukraine overheated
and melted with a steam explosion and a fire. A large amount of
radiation was released and many firefighters were killed by radiation
poisoning. Most of the radiation came from elements with a short
half-life so most of the radiation was gone after a few weeks.
The government decided to evacuate all people from areas which
were expected to result in a radiation exposure of more than 35 rem in
a lifetime. Question? What if evacuating people results in
stress and this increases drinking and smoking? These are well
known causes of cancer and heart disease. Are you making a bad
situation worse by evacuating people?
The Linear Hypothesis:
Most governments and health professionals assume a linear
hypothesis. This means that the only "safe" level is no radiation
(0 rem), and that for every additional rem there is an increased chance
of cancer. Many experts believe that this is wrong, perhaps low
levels do not add to the likelihood of cancer and there is a level
below which (say 6 rem) that has no effects, this actually fits the
data better. The implications of these two hypotheses are
discussed.
C9 Radioactive Decay
A short physics lecture on radioactive decay and half-lives.
The dangerous isotopes are those with medium half-lives.
Those with a short half-life burn through their radioactivity
quickly and after a few weeks they are burned-out. Those with a
long half-life emit radiation very slowly, over thousands or millions
of years. You would have to live with Uranium-238 for millions of
years before you would get a significant dose of radioactivity.
The rest of the chapter is mainly devoted to debunking myths.
C10 Nuclear Weapons
There are 3 types of "atom bombs". Uranium (U235), very
hard to purify as U235 is mixed 1/140 with U238 but easy to make a bomb
with. Plutonium, easy to get if you have a nuclear reactor but it
is very difficult to make into a bomb. And Hydrogen which is very
powerful but need either a Uranium or Plutonium bomb to set it off and
it itself is very difficult to make. A discussion of chain
reactions and the building of the early atomic weapons and fallout.
He makes the point that numerous smaller atomic weapons are more
destructive than just a few larger weapons.
C11 Nuclear Madness (p 146)
C12 Nuclear Power
C13 Nuclear Waste
C14 Controlled Fusion
IV SPACE
C15 Space and Satellites
C16 Gravity Applications
C17 Humans in Space
C20 The Greenhouse Effect
C21 A Very Likely Cause
C22 Evidence
C23 Nonsolutions
C24 The Fruit on the Ground
C25 New Technologies
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1491
Charles C. Mann
Aug 2009 Audio Book
I really should have read this book but I had to do some traveling and
I didn't want any of the readily available alternatives. Writing
a report on a non-fiction book is very difficult if you can't go back
and refer to the original. The author makes four major points:
- In 1491 there were probably more peopled living in the Americas than in Europe.
- The earliest cities in the Western Hemisphere were thriving before the Egyptians built the great pyramids.
- Amazonian Indians learned how to farm the rain forest without
destroying it--a process scientists are studying today in the hope of
regaining this lost knowledge.
- Native Americans transformed their land so completely that
Europeans arrived in a hemisphere already massively"landscaped" by
human beings.
Based on these findings, how could Europeans sail over in small boats
and conquer the native Americans? He makes the point even more
forcefully than Jared Diamond does in Guns, Germs, and Steel
that disease (germs) almost completely wiped out native American
societies shortly after the first Europeans arrived. In many
cases the very first Europeans found large powerful societies awaiting
them when they landed but after they came back a few years later they
were almost completely gone. Perhaps as many as 90 - 95% of the
residents had been killed by disease or starvation and many of the
survivors had retreated inland to family or allied tribes, carrying
disease to them in turn. The guns and steel of the Europeans were
by then quite sufficient to kill any remaining Indians who were not
willing to live as the Europeans wanted them to.
The author did not document his conclusions as well as a scientist
might have but it was a very convincing and readable book.
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liars, lovers, and heroes
Steven R. Quartz & Terrence J.
Sejnowski Oct 2009
Subtitle: What
the new brain science reveals about how we become who we are.
Preface Who are we:
What is it to be a person, to love and to hate? Are we good
or fundamentally evil: What makes us happy? Ultimately, who
can we become? These are some of the questions asked in the book.
Because of the progress in brain science we are starting to get
some answers. Some of the recent tools of brain science are
arrays of tiny electrodes, brain imaging (f MRI), computer simulation,
molecular genetics (the human genome), interactions with human culture
(cultural biology), etc. http://www.liarsloversandheroes.com is supposedly a web site set up by the authors but it does not seem to be operational.
C1 Our Brains, Ourselves
The chapter opens by discussing how disturbing it is to hold a human
brain in your hands. Even medical students who are otherwise
quite comfortable in the presence of a cadaver being dissected
drastically change their behavior when a brain is being removed from a
once living skull. The first chapter bounces all around the
discussion of the brain and thinking about it. They discuss
Alzheimer's, changes in personality called the "gourmand syndrome",
Darwin, social darwinism, sociobiology, Dawkins and the "selfish gene",
Dolly and cloning, brain learning without intellectual realization, and
cognitive neuroscience.
C2 Making Connections
The NIPS conferences (Neural Information Processing Systems) with a
large group of diverse scientists, a brief discussion of the authors
background in neuroscience, chimpanzees, bonobos, and the sense of the
self (the prefrontal cingulate cortex in area 10 of the prefrontal
cortex. The concept of "cultural biology" and why nature vs.
nurture is a false distinction.
C3 How to Make a Human: The 1.6 Percent Solution
Some of the differences and similarities between computers and brain
(nerve) structures. Humans and bonobos share about 98.4% of their
genes. In the 1930's Winthrop Kellogg, a psychology professor at
Indiana University and his wife Luella tried to raise their son and a
young chimp together, treating them as twins. They had
hypothesized that a chimp could be made into a human. What
happened was that using non-verbal behavior the chimp general surpassed
their son except that the chimp never learned any English.
However their son was very good at learning to speak chimpanzee.
One of the main differences was that humans are much better at
observing behavior and copying it. Not "monkey see, monkey do"
but rather "human see, human do."
The brain is an odd mixture of specific hard-wiring and areas that can
change and grow to accommodate new environments. Both a chimp
brain and a human brain are unfinished when they are born but the chimp
brain is mostly complete within 2 years after birth. A human
brain becomes mostly (about 90%) complete after about 5 years.
However parts of the brain close to sense organs become complete
much sooner than those parts farther away. Current belief
suggests that a rich and complex environment is required to complete
the formation of many portions of the brain. Many animals
(plants?) have more complex genes than humans. The difference in
brain size (ratio of brain size to body size) is more one of timing,
our genes keep our brains growing much longer that other animals.
In this way the environment has a much more important effect in
controlling the size and complexity of our brains than in other
animals.
C4 Life on the Far Shore: Crossing the Mental Rubicon
Why do we have right-of-passage ceremonies and how did they develop?
And when did we become self-aware individuals? It seems
obvious to most of us that elaborate burial ceremonies and art work
like those found in Lascaux cave were created by self-aware people who
were very similar to us. As the authors explain it, following the
end of the last ice age the pace of change broke loose from the
geological time line and expanded exponentially. Around 12,000
years ago humans traveled from Siberia to North America and expanded
through the Americas. Farm animals were domesticated around
10,000 years ago along with the rise of agriculture and the appearance
of towns. 5,000 years ago cities with the specialization of
labor, government, and social stratification arose in what is now Iraq.
As the authors see it, evolutionary psychologists see humanity
evolving over millions of years and our being cavemen driving high
powered vehicles. They seem to see our current culture evolving
in concert with our brains.
Bonobos and Chimpanzees separated from their common ancestors between
1.5 and 3 million years ago. They both live in the rain forest
beside the Congo (now called the Zaire) River. Bonobos live on
the southern side with no gorillas and Chimps live on the northern side
beside gorillas. Bonobos have access to high protein-rich buds
and herbs but the gorillas eat most of them on the north side.
Perhaps because of this chimps hunt and kill monkeys for protein
whereas bonobos do not. It has been said that chimps solve sexual
problems with power and bonobos solve power problems with sex.
For the last 50 million years the earth has been slowly and variably
cooling. More recently, over perhaps the last 1.5 to 1 million
years the climate has cycled back and forth between very cold and quite
warm. This seems to have caused a great deal of evolutionary
change in our ancestors. They use the term "cultural biology" to
describe the evolutionary behavior or our ancestors. Our physical
stature has evolved slowly but our culture and our brains have evolved
together and very rapidly.
C5 Between Thought and Feeling: The Mystery of Emotions
Plato had it right all along, he said that the mind was like a chariot
drawn by two horses, one intellect and the other emotion - an unruly
team. Nineteenth-century Romantics saw it as two gods, the
brothers Apollo, calm and serene; Dionysus, wild with drunken
excess. There are many methods and pathways that chemicals and experiences influence our mind.
One example is the drug Ecstasy. It causes certain neurons to
release serotonin which is manufactured using the amino acid
tryptophan. These neurons are located in the dorsal Raphe nucleus
in the brain stem. Serotonin makes us feel relaxed, comfortable,
and happy among other things. Ecstasy is active for around 4 to 6
hours and it uses up most of the serotonin in the brain and then we
become non sociable with fatigue and irritation. It can take weeks
for our levels of serotonin to recover. Prozac also increases
serotonin activity but it acts more slowly. Without sufficient
serotonin levels we may become depressed or aggressive. Many other
drugs modify serotonin levels. Other drugs are mood altering,
another example is noradrenaline (norepinephrine).
The authors make a big deal of the Star Trek character,
Spock. Humans, and in fact all animal life on Earth use chemicals
like these as part of their normal brain chemistry. Spock's
elimination of emotion might work for him but it would not work for any
life forms based on Earth's animals. They all require emotion to
get us going. Spock is compared with TV's super salesmen and with
motivational speakers. The authors point out that other than a
few "pathological cases", the perhaps 10% who be come clinically
depressed sometime during their lifetime and those few manic
individuals (motivational speakers), most of us, around 80%. are
basically happy with occasional highs or lows.
Essential items of brain design, a database of past events and a
mechanism to use that knowledge to make predictions about the future to
guide action to obtain life-enhancing goals. We are very good at
predicting the rewards of an action and comparing this prediction with
the actual results. A single neuron in the bees brain, a cell
named VUMmx1, seems to be responsible for the bees ability to learn
odors. It uses a chemical called octopamine, chemically similar
to dopamine. It seems to be one of the main agents in bees
learning to associate a flower type with nectar. A comparison of
the programming of Deep Blue, the IBM computer that plays chess at the
masters level - but that's all it can do - and other learning programs
that use neural networks to learn how to play other games.
More on brain chemicals, dopamine. Dopamine seems to be involved
in many areas of brain functioning. One study seems to indicate
that dopamine is involved in making predictions and decision
making. Antonio Damasio and Elliot. Elliot was a good
husband and father when he was diagnosed with a large tumor in his
brain. It was removed and with it went a large amount of the
orbitolfrontal cortex. After the surgery Elliot was a different
person. Ignoring a lot of details, he had lost the ability to
process feelings. He could reason about moral issues but he
didn't understand them. He could not use them in managing his own
life.
Abraham Maslow postulated a hierarchy of needs. While the exact
details may or may not be accurate, it is very compelling that humans
have different needs and some are more basic than others. Can a
drug model of beliefs explain more than a rational account?
C6 Becoming You: Genes, Parenting, and Personality
How and why do people differ? They use the examples of the Blue
Angels pilots or John Glenn vs. the Woody Allen character. Babies
are definitely born different. They report that a study shows
that about 20% of babies are born with an inhibited temperament, 40%
have a bold or fearless nature, and the rest are somewhere in
between. It is not clear why differenced in temperament occur but
noradrenaline, serotonin, dopamine, acetylcholine, and their
interactions are all involved. It seems clear that both genetics
and prenatal development play a part. However birth temperament
does not necessarily stay with us, by age 4 years only about 10% of
infants are in the extremes vs. the 60% at 4 months.
At a more basic level less than 3% of births have congenital brain
defects - this low number is undoubtedly related to the fact that 75%
of miscarriages are due to brain malformations. Of newborns with
about 40% of those who die in the first year are due to brain
defects. As people age they move from inborn brain control of
your life to learned control. They call this the frontalization of
behavior as control is mediated by the prefrontal brain
structures. They see personality as being a direct outgrowth of
temperament as we experience life. John Allman at Caltech has
discovered a type of neuron in the anterior cingulate. The
spindle cells as he calls them, are numerous in humans, less so in
chimps, rare in other great apes, and missing in all other animal
species. They begin forming at about 4 months after birth just
when real socialization starts in human babies.
There is a serious disagreement among current researchers regarding the
relative importance of parents vs. other children and the community as
a whole in the socialization and development of the personality of a
child. The authors seem to be firmly on the side of the
environment, there is no single thing called character. Depending
on the social environment we may act very differently. It isn't
so much that either the parents or the world of peers is the most
important, it is that children learn how to live in more than one
context. One of the main ways in which we differ from chimps is
that chimps seem to be incapable of understanding that other chimps are
thinking, feeling creatures just like they are. Humans begin
learning this fairly early and we begin to master it only during
adolescence. Chimps can learn by watching others but there have
never been any reports of a chimp attempting to teach another
chimp. At around 9 months human children begin indicating that
they would like another person do do something for them.
They use a metaphor from T. S. Elliot that likens personal freedom with
a sailboat with reason at the helm and passions filling the
sails. The lower areas of the brain have evolved over the
millennia but the upper hemisphere which separates our behavior from the
apes and other animals has been evolving rapidly for a much shorter
period. The prefrontal cortex is in control but it relies on many
of the structures of the brain stem and midbrain to perform much of the
heavy lifting. The internal linkages have to be recreated anew in
each individual and minor errors can be disastrous in a complex
society.
C7 Friend, Lover, Citizen: The Mystery of Life Together
Why do people sometimes act altruistically, why do some people
sacrifice their own lives for the sake of others? Some,
Aristotle and Darwin called it natural sociability or the social
instinct. Others starting with the Sophists of ancient Greece and
extending to Machiavelli, Thomas Hobbes, John Locke, and Sigmund Freud
believed that acts of mutual aid are a tool used to gain personal
advantage. Our natural state is a war of all against all.
The authors believe that brain science is beginning to start providing
answers or at least telling us which questions we should be
asking.
They start with Thomas Hobbes and his 1651 Leviathan.
Hobbes had two major influences on his thinking, the first was the
beginning of the scientific revolution which was reductive, breaking
things down into their component parts. Previous Christian
doctrine held that societies were organic wholes with individuals a
part of the body of Christ. Individuals derived their identity
from the larger collective vision. Hobbes reversed that.
The second major influence was England's civil war. As he said it
made England a world of "masterless men". They were
self-interested and asocial. They only formed social contracts
out of self-interest.
Locke accepted Hobbes' view of men struggling but he thought it was
between the populace and the King. We owe much of our
Constitution to Locke. Adam Smith also saw this same struggle be
he saw it as primarily economic and believed that the "invisible hand"
of the marketplace as the solution to the problem of individuals
struggling against each other. In part evolution and the
economics of Adam Smith come from the same ideas. Malthus's essay
came out of relating misery and scarce resources created by
overpopulation, Darwin used this same idea in the competition for
resources in natural selection. John Maynard Keynes
commented that The Origin of Species
was just economics couched in scientific language. James Buchanan
who won the Nobel Prize in Economics in 1986 for stating that voters
etc. support policies because of their effect on their private
interests. A competing view, starting with Darwin, held that
altruistic behavior can be explained if the unit of selection were to
be considered the group instead of the individual. Then
individual sacrifice can forward the needs of the group. Other
arguments based on The Prisoners Dilemma and The Tragedy of the Commons pushed thought towards a very powerful argument in favor of individual rational self interest.
Unfortunately, as with many great theories, ugly facts started getting
in the way. Starting in the late 1970's research started showing
that people cooperate at a much higher level than predicted.
Another way of looking at this is the selfish gene concept of Richard
Dawkins. A selfish gene does not imply a selfish person.
The strictly rational economic model of humans, Homo economicus, is not
so much flawed as incomplete. It does explain some behavior but
it does not explain all behavior.
Darwin saw the child-parent bond as being a starting point for natural
morality and social life. In primates - if males are about 30% or
more larger than females, males do not participate in raising young,
less than 20% (or so) larger and males are likely to participate.
Males of chimps and the other great apes are 27% or more larger than
females, males do not help. Humans, about 17%, do help. The
earliest hominid, Australopithecus, at about 35%, probably didn't
help. The next step, Homo habilis, is very similar to modern and
probably did help. This is when the brain expanded rapidly.
Brain size and family groups are probably essential for the growth of
an intelligent being.
The next step would seem to be the ability to enter into long-term
reciprocal relationships with non kin. Brain science is taking
the first steps towards uncovering the biological roots of these
bonds. We have discovered that almost every form of mental
disturbance involves disruptions in social attachments. Current
research suggests that parent-child bonds, pair bonds of romantic love,
and the social bonds of friendship may all have a common root in the
brain. They all activate brain systems that use the chemicals
oxytocin and arginine vasopressin (AVP); endogenous opioids such as the
endorphins, and dopamine. These systems are all found in other
primates but in a brain with expanded and shifted proportions.
The chemicals of sex, testosterone and estrogen, act in many strange
and confusing ways. Somewhat surprisingly, they don't act
everywhere in the brain. Much of the control of sexual makeup
lies in deep aspects of the brain, especially in the
hypothalamus. The authors discuss the various chemicals in
pair-bonding and sex for a number of species and it truly
complex.
The authors discuss the absolute requirement for all young primates to
have caring relationships with parental figures. If this
relationship is blocked most young will be badly damaged. The end
result of severe blocking is almost always death. Lesser degrees
of blocking almost always results in unsocial or antisocial
behavior. In earlier primates the control of parenting behavior
is primarily hormonal and as we move to the great apes and humans
control move to being more cognitive.
They go on to a consideration of friendship. If we operated only
from self-interest, pets would almost never be present, but this is not
the case, we spend huge amounts of money and time interacting with our
pets. A similar relationship exists with the longevity of men vs.
women. Women live longer than men in humans and in almost all
species of monkeys and apes. This seems to be directly related to
how much care giving they provide. In the few species of monkeys
and apes where males provide most of the care of infants, they live
longer than females. In humans taking care of an elderly parent
or even a pet may provide greater longevity. A study in
California showed that people with many strong social ties to others
were much more likely to live longer than those with few social
ties. A fairly large study of social capital and health showed
that with a high degree of civic trust were less likely to die.
They also found that among people who belonged to voluntary
associations the more organizations they belonged to, the lower the
mortality rate.
Even though we thrive on social contact, there can be problems.
It is relatively easy for us to be swayed by clever advertisers,
swindlers, and people who send out scary email viruses. Our need
and acceptance for such human contact can lead us to hyper conformity
and cults. The events at Waco, Jonestown, and Heaven's Gate show
what can happen when our trust is placed on uninformed, greedy, insane,
or evil people.
C8 The Killer Within: From the Solitary Killer to the Killing Crowd
A staple of the nightly news is the killer. Some are organized
groups like Rwanda or Kosovol, some are individuals, some are groups or
ethnic or religious groups. The authors use the imagery of 2001,
A Space Odyssey of a protohuman picking up a bone and clubbing another
protohumans skull, killing him. For many this typifies the
difference between the "Killer Ape" and our more peaceful
relatives. Then in 1974 at Jane Goodall's research center in
Tanzania a researcher watched a group of 8 chimps travel to the
territory of a neighborhood group of chimps, surprise one, chase and
capture it, and beat it until it was almost dead. The group then
left and the beaten chimp limped off and probably died. The
researcher had watched an act of war, a raiding party. Many have
said that the best predictor of aggression in a group is the number of
young males between 15 and 29. But this isn't true, children
perform many more aggressive acts between the ages of 24 months and 36
months of age. The item of real importance is how soon and how
reliably this aggressive behavior is inhibited and replaced with
cooperative and peacemaking strategies. Many pathological
conditions, both physical and cultural can inhibit this
replacement. Lack of maternal care, stress, low serotonin, and
others can contribute. In one study monkeys who were raised in a
standard environment and another group of monkeys who were neglected
were both given small doses of amphetamine. The normally raised
monkeys were hardly effected whereas the neglected monkeys went
berserk, attacking and killing others. Other brain chemicals
which are released during stress, like corticosteroids, literally
attack brain cells causing permanent damage. Corticosteroids
damage the hippocampus which mediates long-term memory and
learning. This may be involved in post-traumatic stress
disorder. Another similar result may be the breaking of the bond
that should exist between knowing the you that performed an action and the you
that must face the results of that action. This is called
dissociation or dissociative identity disorder which is the current
name for what was called multiple personality disorder. As many
of 99% of those who develop dissociation have documented histories of
severe and prolonged trauma during childhood. However, many with
similar behavior problems there seems to be no cultural causation and
we are left with the likelihood of internal brain pathology either
caused by an early injury or genetics.
The authors describe numerous cases where people have been brain
injured and later experience problems with planning for the future and
are deficient in judgent and moral insight, Damasio calls these cases
"acquired sociopathy". The authors don't offer a cause for
"congenital sociopathy". Most put the prevalence of sociopathy at
between 1 and 4% of the population. Most are living in the
general population and often have difficulties with irritability,
argumentativeness, and intimidating personalities which causes others
to avoid them, difficulties in holding jobs, domestic violence, and
traffic offenses. About 20% of the prison population is
sociopathic. Many are self destructive and often injure
themselves. "For these men, then, feeling pain from severe trauma
is better than feeling nothing at all."
Often violence within groups is a sign of social behavior.
Aggressive warfare involves an impressive amount of cooperation among
people. Much of human evolution has involved bringing behavior
mediated by lower brain centers into the control of the frontal
cortex. Many things can go wrong in this process, both
biologically and culturally. Any one and especially where things
happen in both area can cause problems. They describe examples of
how this "human" linkage can be short circuited. The first is the
Robbers Cave experiment. A boys was used for a
psychological/sociological experiment. The boys were divided into
two groups and kept separate. The idea was to keep them apart for
a week to engender a group mentality and then bring them together in
athletic competitions with the expectation that hostility would
develop. However in less than a week they discovered one another
and begged to be able to compete with each other. At the first
baseball game hostilities started. This escalated rapidly until
one group decided to really take on the other group, they gathered
weapons (sticks, baseball bats, rocks, socks filled with rocks).
They tried several methods of reconciling the differences but nothing
worked until they invented a third group that was destroying the camp's
water supply. It got completely out of hand. Then they
discuss Harris and Klebold and the Columbine High School
massacre. Finally they discuss the behavior of soldiers in
wartime. During WW I at Christmas soldiers on opposite sides
would sing carols to each other and call a truce and play soccer with
one another. In WW II only about 15 - 20% or soldiers ever fired
their weapons. In the Korean War the number was up to 95%.
A major difference was in rifle training. In WW I target practice
was on a mowed field at targets, by Vietnam trainees were in full
combat gear in foxholes with man-shaped targets popping up and only
staying up for a few moments. This is similar to many video
games. The marines have customized a version of Doom. It
seems that one of the things that extensive practice with video games
does is to train small groups of cells to instantly react without
having to "think about" it.
C9 Inside Intelligence: Rethinking What Makes Us Smart
The first intelligence test was developed in1904 by Alfred Binet.
It was designed to determine which children were falling behind in
school so that they could be given additional help. However many
people grabbed onto this idea to create tests which were designed more
to separate people into desirable vs. undesirable, typically on social,
racial, and economic grounds. It was also quickly adopted by the
eugenics movement. They report a crisis in education in the late
1800's and early 1900's. A number of new ideas were tried
including some from industry involving the assembly line process and
specific time and activity rules. IQ testing began being used to
classify students, partly for the excuse that they were not smart
enough to learn - we can now ignore our failures.
A number of "facts" about IQ that have been accepted by most people
have been shown to be false, a few of these are that IQ is fixed, after
hitting a maximum - the brain deteriorates continually until death,
athleticism (activity) is either not related or inversely correlated
with brain activity. Another problem with IQ, it is not that what
is measured by an IQ test is not valid and related to human activity, it
is just that we tend to get hung up on a specific measurement and fail
to realize that it is only poorly related to what we are interested in
or that there are other things that are much more directly
related. It has been noticed that scores on IQ tests have been
increasing over the years. It seems unlikely people are getting
that much smarter over the years but something is happening. Are
we becoming more familiar with IQ tests? Is our educational
system getting better? Are we teaching more to the test? Is
our whole society becoming more knowledgeable? New discoveries in
hearing and how sound is processed are showing how specific training
techniques can enable children how to better process auditory data
which increases their ability to understand speech and therefore to
understand written words. IQ and overall achievement became much
lower because of an easily correctable hearing problem that no one
looked for or new anything about.
Earlier results "showing" that intelligence decreased after the 20's
were mostly of different age groups taking the test at the same
time. Longitudinal tests following the same people are showing
much more interesting results. Some of the techniques that can be
used to retrain or improve old brains and to lower the risk of
degenerative brain diseases such as Alzheimer's are to continue
learning throughout life by stimulating the brain, increasing novelty
by trying new things, having a rich family and social life, having a
positive self-model, and by exercising. The 20th century was
very poor for brain maintenance. Factory work with assembly line
processing became widespread and this is particularly deadly for brain
development.
C10 The Search for Happiness
What is happiness, why is it important, what is it? From
Aristotle to Darwin (or at least Darwinism), to Freud. Are we
still Stone Age cavemen? Why did the Soviet Union and Communist
China fail? Perhaps they went about optimizing the wrong
things. The world has changed greatly over the last 2-300
years. Most of us used to live in small villages and now most of
us live in large cities, what does this change about human
relationships? Within the last century we have moved from
satisfying our needs to satisfying our wants - and we have a lot of
advertising companies busy trying to tell us exactly what our wants
are. Although we really didn't know it at the time, our previous
lives fairly well satisfied our needs for community even though at
times our real needs for food, shelter, etc. were not satisfied very
well. The industrial models of the 20th century have done a poor
job of satisfying our needs for community, family, companionship,
etc.
A large number of factors have been blamed for our failure to be
satisfied with our lot in industrial life and it seems safe to say that
all of these reasons play their part but none of them are an
overwhelming choice for the "most important"; TV, assembly lines,
impersonal mass society, remote decision making, etc. One reason
that hasn't been named much in the past is the magic number 150.
This seems to be the approximate number in a group before there is some
need for a hierarchy. Both Hobbes and Locke concerned themselves
with the "rational economic man". Jefferson rejected this in favor of a
more Aristotelian view that humans are spontaneously social and thrive
in cultures in which the social aspects are of great concern. We
are getting more and more evidence that this is the case.
They discuss the requirements for a civil society and how our
technological advances are influencing this. They discuss the
effect of TV and of the internet. And are such changes for the
good or the bad and can we create a more civil society and how can
these technological innovations be incorporated wisely.
Afterward: After September 11
Mohamed Atta, who piloted the Boeing 767 into the North Tower of the
World Trade Center was not a simple tribesman. He had an MS in
Architectural Engineering, his two sisters are university professors
with Ph D's. There are reasons why humans, highly educated or
not, can turn into radical terrorists and kill thousands of
people. Almost anyone can be induced to perform horrendous acts
if they are induced in the right way by an expert, and bin Laden,
Hitler, etc. were experts in this technique. What actions can we
take to reduce the likelihood that additional people like bin Laden,
Hitler, etc. will be created by societies and who we can prevent people
from following them.
The book has 43 pages of notes and an 8 page index.
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