Evolution is the basis for all modern biology and nothing in life makes sense without an evolutionary lens. http://ncse.com/evolution
Congressman Rush Holt (D-NJ) actually submitted a resolution to the House of Representatives to declare February 12th as Darwin Day, which I support, though I have more than a suspicion he has an uphill battle ahead of him on this. Far too many members of Congress think the Earth is less than 10,000 years old, with far too many of them sitting on the House Science Committee. Of course, to be fair, having even one is one too many.
The American Humanist Association is asking people to write their Representatives in support this resolution. You can also celebrate Darwin Day; look for events in your region. And because science is always under fire, why not toss some cash the National Center for Science Education’s way? They are fighting to make sure that some day, an idea like evolution is understood by everyone for what it is: Reality.
Australopithecus sediba ate bark. Scientists analyzing dentition have concluded that they apparently lived almost exclusively on a diet of leaves, fruits, wood and BARK. wth? Others types of hominids in the area ate grasses and stuff, so this could account for the physical diversity in the Austra. group.
Tiktaalik roseae. Everyone’s favorite lobe-finned fish!
Illustration by Jenny Parks.
I went to the coolest lecture by Dr. April Nowell about Neandertals last night. She is a Paleolithic archaeologist from the University of Victoria whose research focuses on the origins of art, symbol use, and language and on the emergence of modern cognition and modern human behavior. I learned so much!
More about Neandertals: http://ngm.nationalgeographic.com/2008/10/neanderthals/hall-text
More about Dr. Newell: http://anthropology.uvic.ca/people/faculty/nowell.php
Cooking made us human! Ash and charred bone, the earliest known evidence of controlled use of fire, reveal that human ancestors may have used fire a million years ago, a discovery that researchers say will shed light on this major turning point in human evolution.
Harvard anthropologist Richard Wrangham has speculated that controlled fires and cooked meat even influenced human brain evolution. He suggests that humans were cooking prey as far back as the first appearance of Homo erectus 1.9 million years ago, just when humans were experiencing major brain expansion, and proposes that cooking allowed our ancestors to evolve larger, more calorie-hungry brains and bodies, and smaller guts suited for more easily digested cooked food.
I just love these prints. Yesterday, I was standing in my backward watching my homing pigeon forage on the ground for seeds. Out of nowhere, a red tail hawk swooped down, grabbed the pigeon and flew away. R.I.P. Commander Squeaks.
Sit a dog in front of a television screen, and it may not always look intently at what it sees. But show a person on that screen who looks directly at the dog and says “hello,” and the canine will pay attention. In fact, a new study shows that a dog will go so far as to follow the gaze of the human on screen when he or she looks to one side or the other—something not even chimps can do.
Read more here: http://news.sciencemag.org/sciencenow/2012/01/in-the-eyes-of-a-dog.html?ref=hp
I love the late Cretaceous! It used to be a big mystery when I was a kid, and there was actually a lot of disagreement between scientists about the evolution of raptors and birds. Evidence has been rolling in for the last 30 years, and there are just so many cool pre-birds (that’s what I call them, most scientists would probably have a better name).
This is Citipati. They were huge (emu sized). At least four Citipati specimens have been found in brooding positions, the most famous is a large specimen nicknamed “Big Mamma” found in the Gobi Desert. All of the nesting specimens are situated on top of egg clutches, with their limbs spread symmetrically on each side of the nest, possibly-feathered front limbs covering the nest perimeter. This brooding posture is found today only in birds and supports a behavioral link between birds and theropod dinosaurs.
They are in the genus oviraptorid, or egg-theives, but they were totally misnamed at first. Oviraptor was originally presumed to have eaten eggs, based on its association with a fossilized nest thought to belong to Protoceratops. The discovery of actual nesting specimens of Citipati with the same types of egg showed that they were likely brooding the eggs, not feeding on them.
1. Citipati brooding behavior
2. Big Momma
3. Big Auntie
4. close up
5. A 1922 illustration incorrectly showing reptilian-like protoceratops guarding “their” eggs from the Citipati.
The transition in human ancestry from Australopithecus, the genus that existed for 2 million years before Homo, has been enigmatic. A key fossil from near the time of this transition is Australopithecus sediba, which is represented by several specimens discovered in a cave in South Africa. Here is a video reconstruction of A. sediba skull, provided by Lee. R. Berger.
Read more/see more on A. sebida at :http://www.sciencemag.org/site/extra/sediba/
Have you noticed that some South American tribes have huge heads? The mystery has been solved! Usually, environmental pressures drive evolution (biotic factors like predators and disease or abiotic factors like altitude, UV radiation, or climate). In the case of the Amazonian Xavánte tribe, sexual selection and isolated cultural practices led to significant changes to their morphology (shape). A full quarter of the tribe’s population was made up of sons of a single chief, Apoena, who had five wives. You can see how being more reproductively successful means that any traits of theirs can quickly come to dominate the population.
Time for bed! The oldest known bedding, sleeping mats made of mosquito-repellant evergreens that are about 77,000 years old, has been discovered in a South African cave. Microscopic analysis of the bedding suggested the inhabitants repeatedly refurbished the mats.
Read more in the Dec. 9th issue of Science: http://www.sciencemag.org/content/334/6061/1322.1.full
A musk ox is not an ox, nor is it musky. It is one of only two arctic ungulates that survived the end of the Pleistocene Era (last Ice Age) and is genetically adapted to survive the harsh climate of the far North. Its long hair skirt, covering a fine wool coat and a 2-inch layer of fat, allows the animal to retain heat during the long, lean winters. They eat lichens, moss and roots buried in the snow, and Arctic flowers in the summer. It has the longest hair of any mammal!
All populations of animals evolve though random mutations in their DNA, which can sometimes be beneficial and add up to major differences over time. Humans are the only ones who adapt with our wits (called acclimatization, when it happens to an individual) and basically live anywhere! These cool glasses are a way that Inupiaq have acclimatized by protecting their eyes from sun and snow glare.
Here’s a story on NPR about human adaptations and cultural evolution: http://www.npr.org/templates/story/story.php?storyId=129604791
Neanderthals had shorter lower legs than we do, leading scientists to theorize that this was an adaptation to the cold times in which they lived, even if it slowed them down.
But two scientists offer a new explanation for those short lower legs: They allowed these early humans to move efficiently across the sloped terrain of their mountainous homes. Instead of being at a disadvantage on rugged terrain, as was generally thought, Neanderthals even may have been at an advantage, depending on the nature of the slope, they found. The research team also found the same connection between shorter lower-leg bones and mountain life among modern animals.
Georges Cuvier was a French naturalist who established extinction as a fact. He also made fun of Jean-Baptiste Lamarck in a famous speech (Lamarck was the acquired-characteristics-being-inherited guy). Let’s face it, Lamarck was a little ridiculous, but Cuvier was kind of a funny guy.
When the French Academy was preparing its first dictionary, it defined crab as, “A small red fish that walks backwards”. This definition was sent to Cuvier for his approval. The scientist wrote back, “Your definition, gentlemen, would be perfect, only for three exceptions. The crab is not a fish, it is not red, and it does not walk backwards.”
