Human Evolution

human evolution

Third hominin coexisted with modern humans and Neanderthals

Modern humans and Neanderthals lived side by side on the Eurasian landscape for tens of thousands of years — but it turns out they weren’t alone, much to researchers’ surprise. A team of researchers has found a hominin bone in a Siberian cave containing DNA that doesn’t match up with either known hominin species at that time, the researchers reported in Nature today, indicating that these humans shared the continent with a third, unknown hominin.

24 Mar 2010

Voices: Redefining humanity through energy use

What is it, exactly, that distinguishes us from other species? The definition of humankind has perplexed scientists, philosophers and theorists for centuries. DNA composition differentiates species in a technical sense, but that definition is hardly satisfying. Certainly there must be something more ethereal that separates us from “lower” forms of creatures. Over the centuries, several definitions have emerged — from using tools to speaking — but have then been proven insufficient in some heuristic way. So I propose another option: manipulating energy.

24 Mar 2010

Benchmarks: November 22, 1859: "On the Origin of Species" published

By David B. Williams

About a decade ago, I was fortunate enough to hold in my hands a first edition of Charles Darwin’s “On the Origin of Species.” The green cover was cracked and frayed. The cardboard backing protruded through the torn corners. I put the book down and stared at it in awe. The owner of this book was Asa Gray, one of America’s greatest botanists, an important early American supporter of natural selection, and a friend of Darwin’s.

23 Nov 2009

New cousin joins primate family tree - but it's also no missing link

Blogging on EARTH

Darwinius — the purported primate “missing link” that made headlines last spring — is back, sort of. Scientists have now found a close cousin of the primate — and they say the new fossil is no more a missing link than Darwinius was.

21 Oct 2009

The vital statistics

Ardipithecus ramidus was a hominid that lived in Ethiopia’s Afar region 4.4 million years ago. After spending more than a decade studying the species, scientists can now provide a sketch of what the hominid looked like:

Brain: Ardipithecus had a brain size similar to that of a female chimpanzee, about 300 to 350 cubic centimeters.

Stature: Standing 120 centimeters tall and weighing 50 kilograms, Ardipithecus was about the size of a chimpanzee.

01 Oct 2009

Not the oldest hominid

At 4.4 million years old, Ardipithecus ramidus is not the oldest known hominid. In 2002, scientists announced they had discovered a hominid skull from the Sahel region of Chad. Named Sahelanthropus tchadensis, the species dates to about 7 million years ago. And a few years earlier, scientists had announced the discovery of several hominid fossils, including a thigh bone, in Kenya that dated to about 6 million years ago. They named the species Orrorin tugenensis.

01 Oct 2009

It's all in the wrist: Humans lack a knuckle-walking ancestor

Though counterintuitive, scientists have turned their attention away from the feet and to the wrist and forearm to better understand how humans evolved upright walking, or bipedalism. African apes are humans’ closest living relatives, and because these apes knuckle-walk, some paleoanthropologists have suggested that African apes and humans share a knuckle-walking ancestor. A new study, however, reveals that lumping the locomotion of all African apes together is a mistake: Knuckle-walking may have evolved more than once in the ape lineage.

01 Oct 2009

Before Lucy: Older hominid Ardi challenges thinking about human evolution

Lucy, the 3.2-million-year-old Australopithecus afarensis fossil, has long been the poster child for early human evolution. But now she’ll have to share the spotlight with an even older hominid. After spending the last 15 years studying an ancient hominid species about the size of a chimpanzee, scientists revealed details about the 4.4-million-year-old Ardipithecus ramidus in a press conference today.

01 Oct 2009

"Missing link" or major hype?

A squirrel-sized primate that lived 47 million years ago in the rainforests of Europe may be the common ancestor of monkeys, apes and humans, according to scientists who announced the discovery of the “missing link” fossil yesterday at a press conference. The well-preserved fossil has been at the center of a whirlwind PR blitz, including a History Channel documentary airing next week and an upcoming book — yet some scientists say the bones don’t live up to the hype.

20 May 2009

Running into the brick wall of Creationism again

I had recently moved to a new community and begun a new job. One night I was dining with some potential new friends. Upon learning that I am both a Christian and a passionate student of geology, one of my dinner mates proclaimed, “So, I suppose you believe in evolution, right? Well, I need to let you know that I HATE evolution.” I somehow managed to keep my cool. “And exactly why do you hate evolution?” I queried. “My minister has taught us that it is false Christian teaching,” she retorted. By that time, I could not hold myself back.

31 Mar 2009

Pages