WE are the missing link!
As with any other species, human populations are shaped by the usual forces of natural selection, like famine, disease or climate. A new force is now coming into focus. It is one with a surprising implication — that for the last 20,000 years or so, people have inadvertently been shaping their own evolution.
The force is human culture, broadly defined as any learned behavior, including technology. The evidence of its activity is the more surprising because culture has long seemed to play just the opposite role. Biologists have seen it as a shield that protects people from the full force of other selective pressures, since clothes and shelter dull the bite of cold and farming helps build surpluses to ride out famine.
Because of this buffering action, culture was thought to have blunted the rate of human evolution, or even brought it to a halt, in the distant past. Many biologists are now seeing the role of culture in a quite different light.
Although it does shield people from other forces, culture itself seems to be a powerful force of natural selection. People adapt genetically to sustained cultural changes, like new diets. And this interaction works more quickly than other selective forces, “leading some practitioners to argue that gene-culture co-evolution could be the dominant mode of human evolution,” Kevin N. Laland and colleagues wrote in the February issue of Nature Reviews Genetics. Dr. Laland is an evolutionary biologist at the University of St. Andrews in Scotland.
Featured in Discover Magazine: The Boskops.
Skulls found of this group had a cranial capacity of 1,980 cc and a child-like face. The combination of a large cranium and immature face would look decidedly unusual to modern eyes, but not entirely unfamiliar. Such faces peer out from the covers of countless science fiction books and are often attached to “alien abductors” in movies.
The combination of a large cranium and immature face would look decidedly unusual to modern eyes, but not entirely unfamiliar. Such faces peer out from the covers of countless science fiction books and are often attached to “alien abductors” in movies. The naturalist Loren Eiseley made exactly this point in a lyrical and chilling passage from his popular book, The Immense Journey, describing a Boskop fossil:
“There’s just one thing we haven’t quite dared to mention. It’s this, and you won’t believe it. It’s all happened already. Back there in the past, ten thousand years ago. The man of the future, with the big brain, the small teeth. He lived in Africa. His brain was bigger than your brain. His face was straight and small, almost a child’s face.”
Boskops, then, were much talked and written about, by many of the most prominent figures in the fields of paleontology and anthropology.
Yet today, although Neanderthals and Homo erectus are widely known, Boskops are almost entirely forgotten. Some of our ancestors are clearly inferior to us, with smaller brains and apelike countenances. They’re easy to make fun of and easy to accept as our precursors. In contrast, the very fact of an ancient ancestor like Boskop, who appears un-apelike and in fact in most ways seems to have had characteristics superior to ours, was destined never to be popular.
There is some interesting about how dance is indicative of physical health and fertility, but I particularly loved Chris Hampson’s take on some new research about why older guys dance poorly.
It is one of the mysteries of life, then, that such dexterity and skill ultimately, and invariably, leads to a phenomenon widely known as Dad Dancing.Sadly, you’ve all seen it.Grown men who should know better hog the dance-floor at wedding receptions and indulge in cringe-worthy, awful antics that make other adults shrink away, and children wish they had eloped.It is worse than those school pick-up moments when some spotty, gangling teenage child you have rushed to collect asks you to wait in the car because your very existence embarrasses them.
Dad Dancing is our revenge.
But now an academic in the U.K. has come up with another explanation. Evolution.It seems that middle-aged wannabe “John Travolta dancing” is nature’s way of warning lovely and nubile young women to look elsewhere. Who knew?It is, according to Dr. Peter Lovatt, the psychologist behind the study, a way of sending out a message: “Stay Away. I’m not fertile.” They then hurry off to look for a young man who is at his sexual peak, so they can have babies and save the species.Dad Dancing is, it seems, like fly spray – a repellant intended to kill off any sexual desire.Why you would need an academic study to tell you that I don’t know. I have yet to hear of any lovely 18-year-olds who long to dally with middle-aged, balding, boring men who are several years older than their dad.Lovatt has apparently compared the dancing styles and confidence levels of nearly 14,000 people – more even than the judges on Dancing with the Stars. (Where did he find the time?) It seems that men between 35 and their 60s typically attempt complex dance moves with limited co-ordination. Women gauge the males’ testosterone levels by assessing the style and energy of their moves.
Then, according to this theory, they apparently make a dash for the nearest Boy Scout camp.
In a somewhat unflattering comparison, Lovatt explains: “It’s like an apple that’s going brown – you want a fresh green one instead.”
A brown apple? Me?
The title of this post almost rhymes. But that’s not important – what IS is the fact that we’ve found yet another animal that uses tools. Huzzah!
I’m using Science Daily‘s article:
Scientists once thought of tool use as a defining feature of humans. That’s until examples of tool use came in from other primates, along with birds and an array of other mammals. Now, a report in the December 14th issue of Current Biology, adds an octopus to the growing list of tool users.
The veined octopus under study manages a behavioral trick that the researchers call stilt walking. In it, the soft-bodied octopus spreads itself over stacked, upright coconut shell “bowls,” makes its eight arms rigid, and raises the whole assembly to amble on eight “stilts” across the seafloor. The only benefit to the octopus’s ungainly maneuver is to use the shells later as a shelter or lair, and that’s what makes it wholly different from a hermit crab using the discarded shell of a snail.
“There is a fundamental difference between picking up a nearby object and putting it over your head as protection versus collecting, arranging, transporting (awkwardly), and assembling portable armor as required,” said Mark Norman of the Museum Victoria in Australia.
Julian Finn, also of the Museum Victoria, said the initial discovery was completely serendipitous.
“While I have observed and videoed octopuses hiding in shells many times, I never expected to find an octopus that stacks multiple coconut shells and jogs across the seafloor carrying them,” he said.
In recalling the first time that he saw this behavior, Finn added, “I could tell that the octopus, busy manipulating coconut shells, was up to something, but I never expected it would pick up the stacked shells and run away. It was an extremely comical sight — I have never laughed so hard underwater.”
After 500 diver hours spent “under the sea,” the researchers observed the behavior of 20 veined octopuses. On four occasions, individuals traveled over considerable distances — up to 20 meters — while carrying stacked coconut shell halves beneath their body.
“Ultimately, the collection and use of objects by animals is likely to form a continuum stretching from insects to primates, with the definition of tools providing a perpetual opportunity for debate,” the researchers concluded. “However, the discovery of this octopus tiptoeing across the sea floor with its prized coconut shells suggests that even marine invertebrates engage in behaviors that we once thought the preserve of humans.”
All the news came out last week about the FOXP2 gene, but I can’t help and post it here a week late anyway:
Chimps, our nearest relative, don’t talk. We do. Now scientists have pinpointed a mutation in a gene that might help explain the difference.
The mutation seems to have helped humans develop speech and language. It’s probably not the only gene involved, but researchers found the gene looks and acts differently in chimps and humans, according to a study published online Wednesday by the journal Nature.
Lab tests showed that the human version regulated more than 100 other genes differently from the chimp version. This particular gene — called FOXP2 — mutated around the time humans developed the ability to talk.
“It’s really playing a major role in chimp-human differences,” said the study’s author, Daniel Geschwind, a professor of neurology, psychiatry and human genetics at the University of California, Los Angeles. “You mutate this gene in humans and you get a speech and language disorder.”
This tells you “what may be happening in the brain,” he said.
A recent study of mummies found a significant number of the elite mummies (which most were) had clogged arteries, calcification of vessels, and other symptoms of heart disease and obesity.
This has been found before, but this is the largest study so far.
The BBC article I read suggested it was caused by the supposed large amounts of fatty meats being eaten by the elite.
However, as I suspected he might, Rafe said “There’s currently a bit of discussion on GNXP (Gene Expression). Michael Eades, auther of Protein Power, has published in the past showing that the Egyptian elite were in fact obese quite regularly, and attributes it to a diet that was very high in grains combined with a sedentary lifestyle, not the high in meat diet proposed in the BBC article.”
Quoted from Science Daily: “UC Irvine clinical professor of cardiology Dr. Gregory Thomas, a co-principal investigator on the study, said, ‘The findings suggest that we may have to look beyond modern risk factors to fully understand the disease.'”
Poor guys get in trouble for everything.
Seriously, people, can’t we take a little responsibility?
(total side note, but I mean it! Some student is suing her college because she can’t find a job. In a recession. After less than three months of searching. Grow up!)
First, another possible missing link candidate, and NOT the guy from Germany that got everyone in a tithy.
Next, how primates trick their friends into giving them food.
Finally, the latest trend in pick-up tricks…pick-up sticks!
I just thought this was interesting; kids crave sugar the most, or love the sweetest juices, when they’re growing the fastest. Cravings for super sweet things tends to die down around 16, around the age that most of us significantly slow or even stop growing.
Very cool study that I would have loved to have been in as a kid. Actually, according to my mother I didn’t like very many sweets, AND I am only 5’2″. Coincidence? Hmm…