Witness to Evolution

1. Witness to Evolution

2. Witness to Evolution • Peppered Moth • 2 types: dark vs. light light Peppered moth

3. Peppered moth: Evolution in action Year% dark% light 1848595 1895982 19951981 clean air, light-colored bark pollution, dark-colored bark Clean Air Act, light-colored bark industrial melanism

4. Peppered moth • Why did the population change? • early 1800s = pre-industrial England • low pollution • lichen on trees = light colored bark • late 1800s = industrial • factories = soot coated trees • killed lichen = dark colored bark • mid 1900s = pollution controls • clean air laws • return of lichen = light colored bark

5. What data from the Genome Project can tell us about evolution of humans

6. Chromosome Numbers in the great apes: human (Homo)46 chimpanzee (Pan) 48 gorilla (Gorilla) 48 orangutan (Pogo) 48 Change in chromosome number? If these organisms share a common ancestor, then is there evidence in the genome for this change in chromosome number

7. Fusion Homo sapiens Inactivated centromere Telomere sequences Ancestral Chromosomes Chromosome Numbers in the great apes (Hominidae): human (Homo) 46chimpanzee (Pan) 48gorilla (Gorilla) 48orangutan (Pogo) 48 Centromere Telomere Testable prediction:If common ancestor had 48 chromosomes (24 pairs) then humans carry a fused chromosome; orIf common ancestor had 46 chromosomes (23 pairs) then apes carry a split chromosome.

8. Human Chromosome #2 shows the exact point at which this fusion took place “Chromosome 2 is unique to the human lineage of evolution, having emerged as a result of head-to-head fusion of two acrocentric chromosomes that remained separate in other primates. The precise fusion site has been located in 2q13–2q14.1 (ref. 2; hg 16:114455823 – 114455838), where our analysis confirmed the presence of multiple subtelomeric duplications to chromosomes 1, 5, 8, 9, 10, 12, 19, 21 and 22 (Fig. 3; Supplementary Fig. 3a, region A). During the formation of human chromosome 2, one of the two centromeres became inactivated (2q21, which corresponds to the centromere from chimp chromosome 13) and the centromeric structure quickly deterioriated (42).” Homo sapiens Inactivated centromere Telomere sequences Chr 2 Hillier et al (2005) “Generation and Annotation of the DNA sequences of human chromosomes 2 and 4,” Nature 434: 724 – 731.

9. In case you had any doubts…

10. Evolution is "so overwhelmingly established that it has become irrational to call it a theory." -- Ernst Mayr What Evolution Is2001 Professor Emeritus, Evolutionary Biology Harvard University (1904-2005)

11. Survival of the Fittest