When
you talk to a biochemist or biologist at a university level these
days about the "evolutionary debate" they're likely to
laugh; after all if you are knowledgeable modern scientist, you know
that the vast body of molecular, genetic, fossil, anatomical, and
field biology evidence all points to the same thing -- that organisms
evolved via natural selection and genetic drift over the last 3
billion years.
More evidence may not
convince skeptics,
but for those interested in science an incredible
discovery was made this year. Paleontologists digging
in South Africa have unearthed a pair of partial hominid
skeletons that represent a new species on the human evolutionary
tree.
Scientists have named the
creatures Australopithecus
sediba.
The species lived in Africa less than 2 million years ago. In
contrast with "Lucy", the 3 million year
old Australopithecus
afarensis fossil
found in Ethiopia in 1974, the new skeletons are taller and are less
ape-like in facial structure.
Researchers estimate that the
pair lived between 1.78 and 1.95 million years ago. They walked
upright, like later hominids and had long forearms and short
fingers. They also had very long legs, which the
paleontologists believe were conducive for running across the African
wilderness, which would be a key to escaping predators and finding
food.
Dr. Lee Berger from the University of the Witwatersrand
in Johannesburg and Dr. Paul Dirks from Australia's James Cook
University led the team that found the pair in a collapsed cave in
South Africa's Malapa cave complex.
They speculate
that our unfortunate ancestors died quite young. One skeleton,
a male, appeared to be only 10 and 13 at his time of death, while a
second, a female, appeared to be in her late 20s or early 30s.
It is thought that the pair was searching for water, and likely fell
into the cave on accident, receiving fatal injuries.
The pair
did have some ape-like features, according to Dr. Berger. He
says their brains were "remarkably small" based on the
skulls discovered and states, "they could still climb trees
[and] they were very competent walking ... on the ground."
The
fossils have smaller teeth and advanced pelvises, though, hallmarks
of human evolution. Still Dr. Berger prefers that people don't
call them a "missing link", which he feels is an outdated
term. He remarks, "I don't like the use of that term.
[It's a] Victorian-era [term that] implies some (specific) chain of
evolution."
He does say the fossils will offer an
incredible contribution to understanding how humans evolved into our
current form. The truly exciting part, he revealed, is that
there are several other partial hominid skeletons that were
discovered, but have not yet been unearthed. In addition to the
hominids, a saber-toothed cat, a brown hyena, and a wild dog were
also found among the remains.
Dr. Berger and Dr. Dirks
co-authored two journal papers on the discovery in the prestigious
AAAS journal Science.
The papers can be found here and here,
respectively.
Some skeptics in the U.S. and abroad continue to
denounce paleontology. For most, it's due to religious reasons,
as they find the idea of evolution "sinful" due to its
contradiction of literal interpretations of text found in The
Torah, The Bible, and The Koran, and other religious works.
The
name itself represents a perhaps humorous double meaning in terms of
scientific theory and religious beliefs. In the local language
Sotho "sediba" means "spring."
However, many note its close similarity to the word "sebida", which means "sin" in Sumerian. In Sumerian
"sebida" refers, more
specifically, "a religious sin that entails the anger of the
gods and a stain upon the soul." To some, that's exactly
what the new skeletons represent, and perhaps researchers thus used
the name to both describe what they feel the skeletons represent (the
"spring" from which man sprung) and to poke a bit of fun at
these in the public who are abandoning the scientific process.