How old am I? Exam #1 F 2/13 Bonuses posted
1.7 million-year-old human ancestor
DNA is passed from generation to generation, and therefore can tell us about relationships between species. Fig 34.40
How are we related to our ancestors, and where did we come from? Fig 34.42
More than 10,000 years ago: Hunter-Gatherer
~10,000 to 200 years ago: Farming-Ranching
Last 200 years: Industrialization
Hunter- Gatherer Agricultural Industrial
The earth is covered in humans. How did this occur?
Human DNA is divided into 46 chromosomes (23 pairs)
X 23 in humans X 23 in humans X 23 in humans Each of us are a combination of DNA from mom and dad.
Mitochondria an Animal Cell
mitochondria Only the egg provides mitochondria to the offspring.
Mom provides % and Dad provides % of DNA to offspring. … because Mom provides 100% of mitochondrial DNA
mitochondria Traits coded for by mtDNA are inherited only through mother
Mitochondrial DNA comparisons can be used to trace ancestry:
Tsar’s Family During the Bolshevik revolution, the Tsar’s family was captured and executed.
Tsar’s Family There are many stories about what happened to their youngest daughter Anastasia
Anna Anderson, claimed she was Anastasia
Anna Anderson claimed she was Anastasia, but tests of her mtDNA and one of Anastasia’s maternal relatives did not match.
For more info check out: Or the book “Seven Daughters of Eve” by Bryan Sykes
When did these migrations take place?
Non-Coding DNA is used for comparisons between individuals
Fig 1 Only DNA that is successfully passed on can be used to trace the past.
Fig 1 and 4 As DNA is passed on mutations take place
Fig 4
By determining the average time between mutations, we can estimate the time of the last common ancestor.
Fig 4 The mutation rate in human mtDNA is one nucleotide change per 20,000 years. OR A difference of one nucleotide between two people indicates a common relative 10,000 years ago.
Multiregional hypothesis “Out of Africa” hypothesis Two hypotheses about the origin of H. sapiens
7 Daughters of Eve, fig. 1 Relationships of different populations using mtDNA ~150,000ya
Multiregional hypothesis “Out of Africa” hypothesis Two hypotheses about the origin of H. sapiens X
7 Daughters of Eve, fig. 2 Relationships of different people using mtDNA.
7 Daughters of Eve, fig. 2 Relationships of different people using mtDNA.
7 Daughters of Eve, fig. 2 Relationships of different people using mtDNA.
7 Daughters of Eve, fig. 2 From Science v298 12/20/02 pg % of genetic variation within population. 3-5% of genetic variation occurs between populations. Relationships of different people using mtDNA.
“Man’s Most Dangerous Myth: the Fallacy of Race” by Ashley Montagu
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