Quote: Bill Bryson
Posted: August 24, 2011 Filed under: Early Man, Quotes Leave a comment »
“Consider the fact that for 3.8 billion years, a period of time older than the Earth’s mountains and rivers and oceans, every one of your forebears on both sides has been attractive enough to find a mate, healthy enough to reproduce, and sufficiently blessed by fate and circumstances to live long enough to do so….”Not one of your pertinent ancestors was squashed, devoured, drowned, starved, stranded, stuck fast, untimely wounded, or otherwise deflected from its life’s quest of delivering a tiny charge of genetic material to the right partner at the right moment in order to perpetuate the only possible sequence of hereditary combinations that could result — eventually, astoundingly, and all too briefly — in you.” — Bill Bryson (A Short History of Nearly Everything)
Thanks to Kathryn for sharing!
Brain over brawn is the key to survival
Posted: July 15, 2011 Filed under: Dinosaurs, Early Man, Nature, Science, Technology Leave a comment »>
By Canadian Press David Suzuki With Faisal Moola, David Suzuki Foundation.
Many people say George Wald was the greatest lecturer in Harvard’s history. He was certainly the best I’ve heard. Dr. Wald won a Nobel Prize in 1967 for his work on the biochemical basis of colour vision. He and I became friends in the 1970s because we shared a common concern about the misapplication of science, especially during the war in Vietnam. Dr. Wald once captivated me with a story he told:
For close to 150 million years, dinosaurs dominated the planet, and they were impressive. They were huge animals, armed with weapons like spikes on their tails, giant claws, and razor-sharp teeth. They were covered with armour plates. They seemed invincible, and when they roamed the Earth, other creatures fled in terror. But they had a fatal flaw: a tiny brain in relation to their body size. Despite their impressive traits, they disappeared – victims, in part, of their low brain-to-brawn ratio.
About 64 million years after the dinosaurs went extinct, a beautiful animal appeared on the plains of Africa. This animal stood upright and walked on two legs, and its skin was free of fur. Unlike the plentiful wildebeest, this animal was rare. It wasn’t as big as a hippo. It wasn’t even as fast as an elephant. It wasn’t as strong as a chimpanzee, and it couldn’t see like an eagle, smell like a dog, or hear like a gazelle.
But those first beautiful humans were endowed with the highest brain-to-brawn ratio ever achieved, and in only 150,000 years, they had spread to every continent on Earth. Humans eventually outnumbered other mammals on the planet. Their high brain-to-brawn ratio served them well as they learned to domesticate plants and animals, and to live in environments as varied as Arctic tundra, deserts, coral atolls, mountain slopes, wetlands, and forests of every kind.
But then they invented guns and cannons and their brain-to-brawn ratio fell. They got into cars, tanks, and planes, and dropped napalm and nuclear bombs. And with each innovation, the brain-to-brawn ratio sank toward that of the dinosaurs.
I love Dr. Wald’s story because it encapsulates much of our dilemma. The human brain was the critical factor that more than compensated for our lack of physical and sensory abilities. We had a vast memory, we were observant and curious, and we were creative. In the past, our innovations such as the needle, bow and arrow, and pottery had huge repercussions but took centuries to evolve into the culture.
Agriculture was the big shift that released us from being nomadic hunter-gatherers to farmers and village dwellers. Then the Industrial Revolution heralded a massive change. In only two centuries, people were able to harness the cheap, portable energy of fossil fuels to create machines of incredible power. In the movie Avatar, the giant robots have no heads, a symbol of what we have become as a species. We have acquired vast technological power but far too little of the brainpower or wisdom needed to use that power well.
Consider this simple example. When New Zealand fishers discovered a fish called orange roughy in deep-sea waters, they thought they had hit a bonanza. Technology to fish the deep sea – radar, sonar, GPS, freezers, giant nets – enabled them to exploit the abundant fish in massive numbers. Despite the fact that these were a new target species about which virtually nothing was known, the animals were taken in vast quantities. It’s called “harvesting” but it was really a “mining” operation. Only years later did we learn these fish live more than a hundred years and grow and mature far more slowly than inshore species.
When was the last time you ate orange roughy? They have been nearly wiped out all around the globe because our technology was too powerful in relation to our knowledge. We didn’t consider our limitations, which should have caused us to be far more cautious and conservative. The technology meant that brain-to-brawn sank toward a level closer to that of the dinosaurs.
Technology can provide great benefits, but unless we learn to use our heads in applying our technologies, we will also go the way of the dinosaurs.
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David Suzuki is a scientist, broadcaster, author, and chair of the David Suzuki Foundation. Faisal Moola is the director of science at the foundation (www.davidsuzuki.org).
Thanks to Michele for sharing!
Blue-eyed humans have a single, common ancestor
Posted: October 14, 2010 Filed under: Early Man, Research, Science Leave a comment »
ScienceDaily — New research shows that people with blue eyes have a single, common ancestor. A team at the University of Copenhagen have tracked down a genetic mutation which took place 6-10,000 years ago and is the cause of the eye colour of all blue-eyed humans alive on the planet today.
What is the genetic mutation
“Originally, we all had brown eyes”, said Professor Eiberg from the Department of Cellular and Molecular Medicine. “But a genetic mutation affecting the OCA2 gene in our chromosomes resulted in the creation of a “switch”, which literally “turned off” the ability to produce brown eyes”. The OCA2 gene codes for the so-called P protein, which is involved in the production of melanin, the pigment that gives colour to our hair, eyes and skin. The “switch”, which is located in the gene adjacent to OCA2 does not, however, turn off the gene entirely, but rather limits its action to reducing the production of melanin in the iris – effectively “diluting” brown eyes to blue. The switch’s effect on OCA2 is very specific therefore. If the OCA2 gene had been completely destroyed or turned off, human beings would be without melanin in their hair, eyes or skin colour – a condition known as albinism.
Variation in the colour of the eyes from brown to green can all be explained by the amount of melanin in the iris, but blue-eyed individuals only have a small degree of variation in the amount of melanin in their eyes. “From this we can conclude that all blue-eyed individuals are linked to the same ancestor,” says Professor Eiberg. “They have all inherited the same switch at exactly the same spot in their DNA.” Brown-eyed individuals, by contrast, have considerable individual variation in the area of their DNA that controls melanin production.
Professor Eiberg and his team examined mitochondrial DNA and compared the eye colour of blue-eyed individuals in countries as diverse as Jordan, Denmark and Turkey. His findings are the latest in a decade of genetic research, which began in 1996, when Professor Eiberg first implicated the OCA2 gene as being responsible for eye colour.
Nature shuffles our genes
The mutation of brown eyes to blue represents neither a positive nor a negative mutation. It is one of several mutations such as hair colour, baldness, freckles and beauty spots, which neither increases nor reduces a human’s chance of survival. As Professor Eiberg says, “it simply shows that nature is constantly shuffling the human genome, creating a genetic cocktail of human chromosomes and trying out different changes as it does so.”
University of Copenhagen (2008, January 31). Blue-eyed Humans Have A Single, Common Ancestor. ScienceDaily. Retrieved March 26, 2010. Source
>For Early Man, It Wasn’t Easier Being Green
Posted: October 7, 2010 Filed under: Early Man, Nature, Research Leave a comment »>
Archaeologists who study early hunter-gatherer societies are discovering that even the simplest cultures altered their environments, whether they meant to or not.
For example, aboriginal people in Australia burned huge areas to change the landscape so they could hunt animals more easily. Perhaps the most famous example is the way mastodons and giant sloth and other ice-age animals were killed off by roving bands of hungry humans.
Torben Rick, an archaeologist at the Smithsonian Institution in Washington, says the notion of hunter-gatherers living in perfect harmony with their environment is going the way of the dodo. He says he’s discovered that indigenous people even altered America’s coastlines, thousands of years ago.
In a big, sunny laboratory at the Smithsonian, Rick pulls a palm-sized shell out of a plastic bag to show what he means.
“These are red abalones,” he says. “This one is 6,500 years old.” He says people living on the islands of California dumped these shells after eating the abalone and, unknowingly, became “dune-builders.”
“So there might have been a five-foot dune there at one time right above the beach,” Ricks says, “and a group of hunter-gatherers came in, lived on top of that dune, dumped their refuse there and left. And this creates a pavement there that anchors that sand.”
Small dunes eventually became big ones, built up like a layer cake, with trash dividing each layer.
Intentional Changes
Then there were intentional changes that people wrought, like the clam gardens of the Pacific Northwest.
People built rock walls into the ocean shallows.
“What these rock walls do,” says Rick, “is they create behind them an area of sandy substrate that’s really good for clams. You can kind of think of them like a terraced garden.”
Rick has also found layers of sea otter bones thousands of years old in California’s Channel Islands. The layers above just had sea urchin remains. He thinks people killed the otters because they ate too many shellfish. Since otters also prey on sea urchins, the urchin population exploded. All those urchins ate up the kelp forests, creating what Rick calls an “urchin barren.”
Changes Can Lead To Disaster
Rick says intentionally or not, hunter-gatherers altered the environment for a long, long time, long before agriculture emerged. University of Nebraska anthropologist Raymond Hames, who studies how people interact with their environment, says they had no choice.
“The take-home point to some extent is that humans do things to make their life easier,” Hames says. “It was really hard to make a living back then, so you know, you took advantage of the knowledge and skills you had in order to make the environment useful to you.”
Hames says sometimes in early human history, changing the environment led to disaster.
“The problem is that your successes lead to population growth, which then leads to more pressure on the system to produce more resources,” he says. “Your successes can set you up for even greater failures.”
Many archaeologists argue that societies like the Easter Islanders and the Mayans suffered after over-exploiting their forests and land.
Rick notes that human activity is now threatening places like the Everglades and the Chesapeake Bay. Scientists are trying to restore them, but to what condition? He says archaeology can provide snapshots of what these places looked like at different moments in time, and how much people had altered them.
by Christopher Joyce of National Public Radio
>Why are Humans and Dogs so Good at Living Together?
Posted: October 2, 2010 Filed under: Animals, Early Man Leave a comment »>
Dogs have a special chemistry with humans that goes back many tens of thousands of years. Researchers investigated this special evolutionary relationship from a number of different angles. Their results are surprising.
The social unit
Domestic dogs are descended from wolves so recently that they remain wolves in all biological essentials, including their social behavior. Wolf packs have some intriguing parallels with human families:
They are territorial.
They hunt cooperatively.
Pack members are emotionally bonded and greet each other enthusiastically after they have been separated.
In a wolf pack, only the alpha male and female are sexually active even though other pack members are sexually mature.
The social adaptations of dogs and humans are similar enough that dogs can live perfectly happy lives surrounded by humans and vice versa. Dogs are pampered with the best of food and medical care, frequently sleeping in their owners’ comfortable beds.
A family member
Why do people lavish so much care on a member of an alien species? A short answer is that on an emotional plane, families do not see the dog as alien. According to John Archer (1) of the University of Central Lancashire, who has conducted a detailed study of dog-human relations from an evolutionary perspective, about 40% of owners identify their dog as a family member reflecting social compatibility between our two species.
Dogs are extraordinarily attentive and have an uncanny ability to predict what their owners will do, whether getting the dog a meal or preparing to go on a walk. Experiments show that dogs and wolves can be astute readers of human body language using the direction of our gaze to locate hidden food (2) a problem that is beyond chimps.
Dogs also seem attuned to the emotional state of their masters and express contrition when the owner is annoyed, for example. Otherwise, the capacity to express affection -unconditionally – makes the dog a valued “family member.”
Domesticating each other?
Dogs were the first domestic animal with whom we developed a close association. Mitochondrial DNA research suggests that most domestic dogs have been genetically separate from wolves for at least 100,000 years so that we have associated with dogs for as long as we have been around as a species (Homo sapiens). Indeed, some enthusiasts, including Colin Groves of the Australian National University, in Canberra, believe that our success as a species is partly due to help from dogs (3).
According to Groves: “The human-dog relationship amounts to a very long lasting symbiosis. Dogs acted as human’s alarm systems, trackers, and hunting aides, garbage disposal facilities, hot water bottles, and children’s guardians and playmates. Humans provided dogs with food and security. The relationship was stable over 100,000 years or so, and intensified in the Holocene into mutual domestication. Humans domesticated dogs and dogs domesticated humans.”
Relying on dogs to hear the approach of danger and to sniff out the scent of prey animals, our ancestors experienced a decline in these sensory abilities compared to other primates. This conclusion is confirmed by shrinkage of brain regions devoted to these senses (the olfactory bulb and lateral geniculate body).
During the long period of our association, dogs brains have shrunk by about 20 percent, typical for animals such as sheep and pigs who enjoy our protection. Domesticated animals undergo tissue loss in the cerebral hemispheres critical for learning and cognition. If we relied on dogs to do the hearing and smelling, they evidently relied on us to do some of their thinking.
If Groves is correct that dogs have domesticated humans, then the human brain would also have gotten smaller. Surprisingly, human brains have actually shrunk, but by only a tenth, suggesting that dogs got more out of the deal than we did.
By Nigel Barber, Ph.D.
1. Archer, J. (1997). Why do people love their pets. Evolution and Human Behavior, 18, 237-259.
2. Udell, M. A. R., Dorey, N. R., & Wynne, C. D. L. (2008). Wolves outperform dogs in following human social cues. Animal Behaviour, 76, 1767-1773.
3. Groves, C. P. (1999). The advantages and disadvantages of being domesticated. Perspectives in Human Biology, 4, 1-12.
>Video: Monkey Tool Usage Hammer and Anvil
Posted: September 9, 2010 Filed under: Animals, Early Man, Videos Leave a comment »>
From the BBC documentary “Capuchins: The Monkey Puzzle”, narrated by the ever brilliant Sir David Attenborough.
For the full 29 minute documentary, “Capuchins: The Monkey Puzzle”, click here.
>Group Claims to Have Discovered Noah’s Ark
Posted: April 28, 2010 Filed under: Early Man, Research Leave a comment »
Visual approximation
By Amanda Fox
An evangelical group comprised of Turkish and Chinese explorers claims that they think they have potentially made one of the biggest discoveries of the last hundred years – Noah’s Ark. The group that claims to have made this discovery of Biblical proportions is Noah’s Ark Ministries International. At this time they concede they are not 100% sure this is Noah’s Ark, but they do claim to be 99.9% sure.
Noah’s Ark Ministries International claims to have made the discovery on Mount Ararat which is located in eastern Turkey. At this time the team has released no photos, but has submitted an application for United World Heritage status in Ankara to preserve the integrity of the site while further work is being performed.
Gerrit Aalten, a noted Ark researcher, has been included in the process to help verify the legitimacy of the teams claims. Aalten has stated the he felt this was a legitimate discovery based on so many details matching historic accounts of the Ark, and that this particular area has long been thought to be the Ark’s final resting place. He has not staked his reputation to saying this is definitely the Ark with no doubts, but has rather stated that it is a legitimate archaeological discovery.
Early descriptions of the alleged Ark describe several compartments the ream believes were used to house animals. Carbon dating of relics recovered from the site has placed the age of the discovery at around 4,800 years old. They also point out that no human settlement has ever been discovered above 11,000 feet (The alleged Ark now rests at about 13,000 feet) in the locality in question which indicates that it is very highly unlikely they stumbled upon an abandoned ancient settlement.
Before anyone gets too excited about this being the genuine Ark of Noah, there have been many previous claims of its discovery that turned out to be erroneous. What has many people excited about this particular discovery is that this particular location has been believed to be the actual location since 1959 when aerial photographs showed an anomaly in the landscape many believed could only be man made. They further point out the size is indicates the proportions cited in the Bible.
While it is going to take years to unravel this mystery, the excitement for many surrounding this discovery is undeniable – even if it does not prove to be Noah’s Ark. The worry many have at this time is that the faithful see what they want to see without regard for science – and that includes the archaeologists on the team. The discovery of the true Noah’s Ark would potentially have implications that cannot be fully fathomed, and because of that the scientific community is calling for extreme caution before nay further pronouncements are made.
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By Amanda Fox.
>The Origin of the Cat
Posted: April 21, 2010 Filed under: Animals, Early Man Leave a comment »>The Near Eastern wildcat began tagging along with humans on their journeys 10,000 years ago in the Fertile Crescent, according to a new study.
The map shows the historic distribution of the five species of related wildcats, including the Near Eastern wildcat, F.s. lybica. Researchers pinpointed the ancestor of domestic cats by comparing DNA of several wildcat subspecies, including a type of European wildcat pictured above.
Top photograph courtesy Ewan Macdonald, bottom map courtesy Science.
Some say that there are two kinds of people in the world: dog people and cat people. While I don’t want to foster any kind of segregative animosity between fellow humans, it does seem to me that dogs, despite their fewer numbers as pets, tend to have the bigger mindshare. Dogs, not cats, are described as man’s best friend, and you hear of dog-related genetics a fair bit more than you do cat-related science. Not today though.
The reason for this disparity is that although there are hundreds of different varieties of domesticated cats, they don’t show the same spread of sizes and shapes we see in dogs. (Apparently, no one other than me thinks the idea of a Great Dane-sized cat is a good one.) What we do know is that cats and humans have lived together for almost 10,000 years. The earliest evidence of cats and humans together was found in Cyprus and dated at around 9,500 years ago. As to the origins of these early domestic cats, not a huge amount has been known. There are a number of subspecies of Felis silvestris in the wild: F. s. silvestris (Europe), F. s. lybica (Africa and the Near East), F. s. ornate (Middle East and Central Asia), and possibly F. s. bieti (China, although some argue this is a separate species). So which one of these groups did the world’s most numerous pets derive from? A new multinational research effort has found the answer, and it’s published in Science online today.
Carlos Driscoll and his colleagues across the world have collected DNA samples from almost 1,000 different individual cats and looked at different genetic markers to identify common ancestry patterns between domestic cats, purebreds, and wild cats. The data they gathered shows that domestic and purebred cats fall into the same clade as wildcats from the Near East, which matches up well with the archaeological data from Cyprus.
The researchers also worked out the approximate age of the species by looking at the genetic sequences with respect to the rate of mutation in order to calculate a molecular clock. It appears that there were five distinct maternal lineages within the domestic cat clade, as early as 100,000 years ago, predating any evidence of human domestication by an order of magnitude. These lineages all appear within the population of domestic cats.
So there you have it: your house cat, just like our modern civilization, most of our grain crops, and the majority of our domesticated livestock has its origins in the Fertile Crescent.
By Jonathan M. Gitlin.
>New Scan of ‘Neanderthal’ Jawbone
Posted: April 10, 2010 Filed under: Early Man Leave a comment »>
The bone became known as “Kents Cavern 4″. (Image: Torquay Museum)
A piece of jawbone found in a Devon cave is being re-examined by scientists who believe it may be Britain’s first direct evidence of Neanderthal man.
The bone was excavated from Kents Cavern in Torquay in 1927 and was thought to be about 31,000 years old.
But more research showed the Torquay Museum piece could be 40,000 years old.
A computer scan is to be carried out to determine if the bone was put back together correctly after it was found, and to see if DNA can be extracted.
The fragment of maxilla (upper jaw) containing three teeth was unearthed during an excavation by the Torquay Natural History Society.
Radiocarbon dating in the 1980s of Kents Cavern 4, as it became known, showed its age to be about 31,000 years old.
That age was placed in doubt after it was found the bone had been strengthened with paper glue, probably after it was excavated.
But more recent radiocarbon dates for animal bones in cave sediments where the jaw was found, indicate the layer it was in dates between 37,000 and 40,000 years ago.
Now a scan taking six hours will allow a three-dimensional computer model to be created.
‘Distinct DNA’
This will be used to establish whether the jawbone and teeth were put back together correctly when first found and to see if DNA can be extracted.
Nick Powe from Kents Cavern said: “Neanderthal DNA is quite distinct, and if researchers can find enough DNA in a tooth they will be able to establish if it is Neanderthal.
“But it was found in 1927 and hasn’t been looked after as carefully as it could have been back in the 1930s.
“The danger is that some of the processes that were used to reconstruct it for display purposes may have damaged it and DNA cannot be taken out of it.”
If the jawbone is found to be Neanderthal, it would be evidence that Neanderthals spread across Europe and reached Britain far earlier than is currently thought.
