Thursday, January 17, 2008

Spencer Wells Comes to SLA - Live Blogged

Dr. Spencer Wells, Explorer in Residence at NG, heads Human Genographic Project
Goal is to answer the simple question of where people come from. Polled immigrant students on where their parents came from. How different are we, really?
Population geneticist - field trying to figure out the answer to that question.
How do you explain the patterns of human diversity?
Broken into sub-questions:
Are we, in fact, all related to each other?
how did we come to populate every corner of the globe and generate the diversity we see?

Darwin's second book, the Descent of man. In each great region of the world the living...
Darwin answered the question over a century ago, "We came from Africa." But Darwin was talking about ancient ancestry. Didn't address the issue of humans. He was talking about things that happened a long time ago.

Apes appear in Africa 23 million years ago.
Fist African exodus 15 million years ago.
We want to know about the origins of the human species, not apes.
Paleoanthropology - digging things up out of the ground and determining ancestry based on shape. Actually relies on very little data. Completely changes the interpretations of where we came from. Three species of hominids found in the same place. Were living in the same place in the same time. Don't know which we actually descended from.
Usually use shape as the only data. Linneas first gave us binomial nomenclature.
The question of origin is really a genealogical question.
3 billion units of DNA in each human cell.
Nice job of comparing copying a book by hand to copying of genetic material.
When they get passed down through the generations, they become markers of descent.
People are 99.9% the same. comparing genographic information from five people to search for variation.
Imagine the DNA sequences are like real words. We're looking at the variable information.
"FIX" and "CAT"
We count the number of changes to get us back to the common ancestor "DOG."
Africans have been accumulating these mutational changes longer than any other group of people. This means Darwin was correct and humans started in Africa. Left Africa 60,000 years ago.
Showing a map of believed migratory paths.
Book, The Journey of Man and PBS film of the same title.
Genographic Project:
  • Global DNA sampling
  • Public participation
  • A Legacy Fund

Regional offices with the goal of sampling indigenous people.
Between 100 and 300 million indigenous people in the world.
Can go on website and get yourself tested.
Net proceeds to legacy fund to help the indigenous tribes maintain educational and cultural programs.
Migrating from homelands to dominant cultures means a sacrifice of culture. About 6,000 languages spoken in the world today. Maybe only 500-600 languages spoken by the end of the century.
Indigenous cultures tell us about natural sources for treatment medicines. Losing cultural knowledge means losing links to important information.
Participants get deeper knowledge.
Showing information from Miss Hull. Showing a map of the migration of Hull's ancestors. Amazing. Her ancestors killed off the Neanderthals. Traced back to a single female ancestor, most successful female group.
Evolved more in the last 10,000 years than we did in the prev. 100,000.
We will be giving up hunter gatherers because of globalization.
Science and Religion: As a scientist, you have to stay away from religion and be as objective as you can. Average Brazilian has no idea what their ancestry is.
Are we turning back into monkeys? No  evidence we are devolving.
Interesting question to end on.

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