Hot Science
Here are the latest links to some of the things what we think are cool in the
world of paleontology.

Live Science

At WNED in Buffalo New York we held a Live Science event where we went live by Skype to South Africa.  
With the assistance of Dr. Bonita Birch, I was able to show the original sediba fossils to the audience!  This is
probably the first time that such a demonstration of an original hominin fossil has been done to a public
audience in such a way, but it won’t be the last!  Watch the video below.

A New Rock Filled with Mysteries

A few months ago, while working with my wife Jackie on her Ph.D.  we together discovered something quite
amazing. Jackie is a medical Doctor specializing in Radiology (the use of x-rays to examine inside of the
human body) and she is doing her Ph.D.  on using those same x-rays and machines to look inside of the
rocks that come from Malapa to see if she can determine if there are bones inside and what they are. Well,
she has had great success and one of the first big blocks of rock we scanned, one that had in fact been
sitting in my lab for almost three years, had what looks like lots of the remains of a skeleton in it!  You can
read about the announcement of this find and see videos by following this link to the Gauteng Government
website at
http://www.gauteng.net/event/sediba/  .  I was in Shanghai, China when the announcement was
made because we are going to be building a state of the art laboratory at
Maropeng, in the Cradle of
Humankind so that visitors can watch us prepare this block.  In addition, we are going to build a number of
“outposts” at selected museums around the world so that you can visit them and watch the preparation
happen.  You will even be able to eavesdrop on the conversations of scientists as we work and manipulate
robotic cameras so you can watch what’s going on!  It should be an exciting experiment in live Science.  Stay
tuned to Scimania for further updates and live links as we go online, hopefully later this year.

The Diet of Sediba

New Questions

Is it possible to learn what a hominin or any creature ate almost 2 million years ago?
What evidence could survive for so long?
What could we learn if we knew about this ancient diet?

Step 1

Find a fossil that has evidence you can explore. That was taken care of by Dr. Berger – see the rest of this
site for the story of Australopithecus sediba. Sediba is unlike any other hominin fossil from the period in that
the teeth are so well preserved we were able to detect tiny traces of what it ate.

Step 2

Assemble your dream team of scientists: experts from around the world who are scientific detectives and can
find clues no one else can see. Here is the lineup:

Leading off is the team captain, Dr. Amanda Henry of Max Planck Institute for Evolutionary Anthropology in
Germany. When you go to the dentist to have your teeth cleaned, the dentist scrapes off material that has
collected on your teeth and hardened. This is called dental “tartar” “calculus” or “plaque” and is not just left
over from last night’s dinner or dessert. Rather, it builds up as bacteria in your mouth combine with food
leftovers (which is why your parents are endlessly telling you to brush your teeth). Dr. Henry studies tartar
from fossils, skeletons, and other ancient remains. She also worked with Dr. Unger and the other two groups
listed below.

Batting second is Dr. Peter Unger, Distinguished Professor of Anthropology of the University of Arkansas who
studies tiny signs of wear and tear in teeth to see what it can tell us about how they were used.

Batting third is Dr. Matt Sponheimer, Professor of Anthropology at the University of Colorado, who studies the
traces of different types, or isotopes, of elements such as carbon to learn about the long distant past.

Batting cleanup is Paul A. Sandberg a graduate student at Colorado who worked with Dr. Sponheimer.

Batting fifth is Dr. Benjamin Passey, Assistant Professor of Geochemistry at Johns Hopkins, who studies the
way climate, geography, and living creatures interacted in the past, and how we can learn about those
connections. He was part of Sponheimer’s group.

Batting sixth Darryl de Ruiter, Associate Professor of Anthropology at Texas A and M, who also worked with
the Sponheimer, Sandberg, Passey crew.

Batting seventh is Dr. Marion Banford, from the Bernard Price Institute for Paleontology at the University of
Witswatersrand who studies the traces ancient plants leave behind – this is called phytolith analysis.

Batting eighth is Dr. Lloyd Rossouw, senior staff scientist of the National Museum Bloemfontein in South
Africa, who worked with Dr. Banford.

Batting ninth is the player-manager Dr. Lee Berger, professor of paleoanthropology at the University of
Witswatersrand, who – along with his son Matthew – discovered the fossilized remains of

Step 3

An Ingenious Combination of Tests

Dr. Henry did one kind of test and oversaw all three: dental microwear, isotope studies of the teeth enamel,
and the plant trace analysis. When we look very closely at how teeth wear, we can draw some conclusions
about what that individual ate. For example, if you eat all soft foods, probably the teeth will be relatively
smooth. If you eat hard foods, the teeth have to do more grinding, and that will be clear to the alert experts.
All teeth carry “signatures” of the foods that helped build them – an examination of your teeth would show a
trained scientist where the cows lived that made the milk which you drank as your teeth formed. Using lasers,
one team captured tiny bits of tooth enamel, and studied them to see what sediba ate as those tooth grew.
Because the teeth were so untouched, close examination of tartar revealed the smallest bits of minerals that
had once been part of plants and were incorporated into the tartar. In a sense it is like examining a chocolate
chip cookie – you find bits of chocolate even though they are now part of the complete cookie. Only the tartar
was nearly 2 million years old, and the “chips” were “visible” only with high tech instruments.

Step 4

What Does It All Mean?

Overview: The diet the researchers found differs from what we assumed about hominin ancestors from 2
million years ago.

The microwear analysis showed different patterns that we have seen on other existing hominin fossils. That
was one clue that sediba had a different diet. It also showed sediba was eating hard foods just before they

The isotope analysis revealed that sediba mainly ate foods that showed a diet typical of animals that either
browse from trees or live in tropical areas (sediba has about the same isotopic signature as a giraffe!). That
wouldn’t be surprising except that other human ancestors of a similar age show signals of eating foods that
are associated with grassland environments in Africa and look more like mixed feeding animals. This study
however,  did not show extensive signs of sediba eating grasses – even though Malapa, where the two
individuals died, was surrounded by at least some grasslands and wasn’t tropical at all.

The plant trace analysis gave the final and clearest picture of sediba’s diet. These studies show traces of
leaves, fruits, some grasses, and other plants including at bark.

There are two big conclusions here from this first-ever direct study of what an ancient hominin ate: 1) sediba’s
diet was selected by choice. Even though it lived surrounded by grassland, it chose to eat foods from the
woodland and forest. In that sense, it ate more like some chimpanzees that return to trees to find food, even if
they pass through grasslands. 2) A team of specialists using high tech instruments, working together and
sharing results could find new kinds of answers no single scientist could discover on his or her own. Dr.
Berger, though, found one more result especially surprising:  “While primatologists have known for years that
primates, including apes eat bark as a fallback food in time of need, I really hadn’t thought of it as a dietary
item on the menu of an early human ancestor.”

Alexander Aronson and Marc Aronson

A Full Body!

Here's a first look at the full body reconstruction of Australopithecus sediba by well known Swiss scientist
Peter Schmid.  Peter has worked on many famous fossils including the well known Lucy skeleton.  Take a look
at how long the arms of sediba are.  This reconstructions stands about 1.3 meters (thats about 4.2 feet tall).  
This skeleton is what we call a "composite" skeleton, which means that it was reconstructed from the different
parts of two or more individuals that were all about the same size, or their body parts had to be scaled to be
the same size as the other individuals.  In this case the skeleton is made up of three individuals - Karabo, the
female skeleton MH-2 and a third adult specimen that hasn't been named yet. The skeleton is on display in
the University of Zurich Museum.

Click the skeleton to Watch Sediba in 3D!

Posted May 12th  by Prof. Berger
Live Science at WNED