Nina Jablonski's analysis of skin color and evolutionary adaptation

TED Talks

Ideas worth Spreading

Nina Jablonski breaks the illusion of skin color (TED2009, 2009)

Nina Joblonski opens by commenting on Darwin's pigmentation and his upbringing. She further speaks of his voyage on the Beagle and his interest in the pigmentation of humans. Darwin did not believe that there was any correlation to skin pigmentation and climate. However, Joblonski points out that if Darwin had access to NASA satellites that he may have come to a different conclusion. One of NASA's satellites has capabilities to monitor the Earth's radiation close to the surface. As a result, researchers today have been able to study skin pigmentation and the exposure to solar radiation and find that there is a perfect gradient and strong correlation between the two.

Therefore, skin color is a product of evolutionary forces as human adapted to their environments and their skin adapt to the levels of radiation that they were receiving. The earliest humans evolved in climates close to the equator that were high in radiation. Types of UV rays are needed to serve important roles in the human body such as the breakdown of vitamin D The lecture points out how different skin pigmentations are better suited to different latitudes. She further points out how this pigmentation can be used to teach people about evolution since it is such a clear example that people can understand.

Figure 1 - UV Light and Skin Color

This lecture is interesting because it points out how superficial skin pigmentation really is to humans. Furthermore, since we live in an age in which science and evolution are under attack from many sources such as creationism and intelligent design, it also points out a simple and clear example that can be used to talk evolution to people that are unacquainted with the science behind it. For example, by pointing out the differences in skin color and how superficial this difference really is, not only can we promote tolerance for other members of our own species, but we can also explain how these differences occurred through evolution and natural selection.

Paul Sereno digs up dinosaurs (TED2005, 2009)

Sereno speaks first of the event that happened approximately sixty five million years in an extinction event known as K/T. He studies evolution on the drifting contents in dinosaurs and other animals. Sereno believes strongly that body size explains much of the evolutionary processes that were occurring during this period such as the fact that they were slow to evolve into trees, air, or into waters. Sereno's group was among the first to identify the dinosaur transition to the air in which evolution began to cover the entire planet with different species. This radiation was one of the most exceptional in history because

Sereno and his teams have been to the far reaches of the Earth to look for fossils that help complete the evolutionary record. Some of the locations he mentions are the Saharan desert in Africa, Morocco, the Arctic region, and many more. His team was even responsible for finding an enormous crocodile that was estimated to be roughly forty feet long. In order to estimate the size they had to look at recent crocodiles. In the presentation Sereno shows a clip from a National Geographic documentary where they are capturing a crocodile they can use for scale references to their fossil. They way that he describes this is that they are trying to piece together different pieces of a puzzle.

Figure 2 - Sereno Capturing a Croc

During the last phase of his presentation, Sereno takes on an entirely different topic. Although he begins by describing his own history, he speaks of his experience in science education. He talks about how he failed out of his school and eventually took classes in art. He then visited a museum and got hooked. Sereno also makes a connection between art and science as he has used a great deal of creativity to make the discoveries that he has. Much of his work has been devoted to science education and runs an organization in Chicago that has had good results in furthering the education of adolescents.

Susan Savage-Rumbaugh: The gentle genius of bonobos (TED2004, April)

Susan Savage-Rumbaugh works with bonobos and refers them as the happiest species on the planet but does not get the coverage they deserve in the news. The reason she states that bonobos have sexual relations that are similar to humans. She makes the claims that the human species is not as special as most people would care to think. Savage-Rumbaugh compares the behaviors of certain indigent tribes to the behaviors of the bonobo and does not see many stark differences in the communities in regards to language and lifestyles.

Wild bonobos often walk upright; sometimes for long distances. The physical frames of the bonobos are not unlike many human ancestors such as the Australopithecus. A video is shown that shows bonobos learning very quickly and that they have advanced communication abilities. They are able to understand their own reflection in a mirror. There parenting ability is exceptional and mimics that of humans. Furthermore, bonobos can also make stone tools and have learned how to work with these tools similar to our ancestors. They can also use communicate through symbols.

Figure 5 - Stone Tools Made by a Bonobo

The interesting aspect in regards to the lecture on the bonobos is that it portrays the importance of culture and diminishes the pedestal that the human species seems to like to place itself upon. For example, it is commonly thought that we are "special" with the development of our cognitive abilities and advanced communication skills, yet the bonobo can also learn many of these skills as well. Therefore, this lecture highlights the importance of community and culture in the development of these skills.