Posted tagged ‘evolution’

Discovery of Oldest Hominid Skeleton Reported

October 2, 2009
Artist's illustration of the skelton of Ardipithecus ramidus.  Image Credit:  J.H. Matternes/Science/AAAS

Artist's illustration of the skeleton of Ardipithecus ramidus. Image Credit: J.H. Matternes/Science/AAAS

Yesterday, the journal Science published a series of papers outlining the discovery of the oldest known hominid skeleton.  The skeleton is that of a small-brained, 110-pound female Ardipithecus ramidus, nicknamed Ardi.   She lived 4.4 million years ago in what is today Ethiopia.  She is over a million years older than the famous Lucy fossil, found in the same region 35 years ago.

The discovery of Ardi raises a number of interesting questions for scientists.  Traditional scientific views, influenced by Lucy, were that human began to walk upright once they left the forest for the savannah.  Ardi contradicts this view.  She  lived in a forested region and walked upright on the ground and on four legs while climbing trees.  Also, given Lucy’s skeleton, scientists hypothesized that the last common ancestor of humans and other great apes had resembled a chimpanzee.  Ardi lacks these chimp-like features.  For more information on this discovery, see National Geographic News.

Fossil Potentially Puts New Twist in Human Evolution

July 8, 2009

A life reconstruction of Ganlea megacanina, a Myanmar primate which lived 38 million years ago in a tropical floodplain similar to today's monkey-filled Amazon Basin of South America.  Image credit:  Mark A. Klingler/Carnegie Museum of Natural History

A reconstruction of Ganlea megacanina, a Myanmar primate which lived 38 million years ago in a tropical floodplain similar to today's Amazon Basin. Image credit: Mark A. Klingler/Carnegie Museum of Natural History

According to research published in the Proceedings of the Royal Society B (Biological Sciences), a new fossil primate discovered in Myanmar may suggest that the common ancestor of humans, apes and monkeys evolved in Asia, not Africa.  According to researchers the new  fossil primate, Ganlea megacanina, has monkey-like jaws and teeth which would potentially place it close in the evolutionary chain to the common ancestor of all primates.  Moreover, this discovery takes the spotlight off of Ida, the fossil discovery announced earlier this year.  For more information on this discovery, see Discovery News.

Ticklish Problem: The Evolution of Laughter

June 5, 2009
Common Chimpanzee (Pan troglodytes).  Photo Credit:  Aaron Logan

Common Chimpanzee (Pan troglodytes). Photo Credit: Aaron Logan

New research on the origin of laughter suggests that humans and apes inherited laughter from a shared ancestor.  Researchers actually tickled human babies, orangutans, gorillas, chimps and bonobos.  They then analyzed 11 components of the sounds each species made when tickled and mapped how the sounds are related to each other.  Once done, the researchers had a map that matched the family tree all the species belong to.  Other scientists argue that the shared ancestor goes back even further, given that other species also produce sounds similar to laughter.  For more information, see Discovery News.

This photo is licensed under Creative Commons Attribution 2.5 License.

Early Primate Ancestor Discovered

May 20, 2009
Darwinius masillae fossil.  Image credit:  PLoS

Darwinius masillae fossil. Image credit: PLoS

Scientists have unveiled a 47 million-year-old fossil from Germany, dubbed “Ida,” that may help illuminate the early evolution of monkeys, apes and humans.  Scientists say the fossil is a transitional species, living around the time the primate lineage split into two groups.  One line would eventually produce humans, primates and monkeys.  The other line would give rise to lemurs and other primates.  The fossil’s formal name is Darwinius masillae, in honor of the anniversary of Charles Darwin’s 200th birthday.  The fossil was originally discovered in 1983, but had been split in half and placed in private collections.  Not until it was recently investigated was the significance of the whole fossil realized.  An analysis of the fossil is detailed in the journal PLoS ONE here.

Sponges Flourished More Than 635 Million Years Ago

March 12, 2009
sea-sponge

Sea Sponge

According to a new study released last month, animal life appeared on Earth tens of millions of years earlier than previously thought.  Using a new dating technique, scientists have evidence that sponges existed at the end of the Neoproterozoic Era.  While over the past several years new research has demonstrated that animal life arose millions of years earlier than prior research demonstrated, this new study pushes back those beginnings much further.  For more information on this study, see here.

Look What Apples Can Lead To. . .

March 6, 2009

ApplesThe introduction of apples to America over 400 years ago has led to interesting new insights into evolution.  Dr. Jeff Feder, a biologist at the University of Notre Dame, and his colleagues recently reported in Science that approximately 250 years ago some hawthorn flies, Rhagoletis pomonella, started to lay their eggs on apples rather than on the small, red fruit of the hawthorn tree.  These flies became genetically distinct from the larger hawthorn fly population.  In turn, the wasps that eat these flies’ larvae also became genetically distinct.  This discovery is important because of the insights it provides into how new species arise.  For more information, see Physorg.com here.

Polar Oceans Rich in Diversity

February 17, 2009

iceberg

Previously thought to be less diverse than the tropical oceans, a new marine census illustrates there is amazing diversity in the polar oceans.  This survey discovered not only new species, but species common to both polar oceans which raises interesting evolutionary questions.  For more information, see the Associated Press article here.