EVOLUTION (part 2) CHAPTER 13 read The Evidence of Evolution

Hutton observed Hadrian’s wall  Built between Scotland and England in A.D.  Still standing with little evidence of erosion.  Observed extinct volcano on which Edinburough castle was built.  Add drawing to notes  Hyperlink to Unitedstreaming Hadrian’s Wall

WONDERED?  "How could a volcano erode in 6,000 years when a wall seems not to have changed in 1,500 years?”  Estimated the Earth's age to be in the millions of years

"Theory of the Earth" published by Hutton "Theory of the Earth" published by Hutton  "The surface of the earth appears as it does because of gradual geologic changes caused by natural processes"  ex. volcanoes, earthquake, erosion, deposition, glaciers, hurricanes Charles Lyell- furthered these ideas in “Principles of Geology”

Uniformitarianism-  _________"theory of uniformity" geological processes of the past and present are the same and are the only processes that influence the way we see the world today.

Catastrophism  ____________ substantial environmental calamities have occurred that have changed the face of the earth. Extinction was followed by repopulation

V. DARWIN and Natural Selection  ( ) Feb 12 same birthday as Lincoln  Studied medicine ministry poor student  5 yr. round the world trip as the ship's Naturalist  H.M.S. Beagle  married his cousin Emma Wedgewood  very seasick weak the rest of his life  collected specimens, fossils, journal and read captain's dinner guest

 his grandfather Erasmus Darwin was interested in evolution  A KEEN EYE FOR OBSERVATION WAS Darwin’s GREATEST ASSET

B. What Darwin knew  1. The earth was old and it had changed, read Hutton and Lyell  2. organisms lived in very special environments  3. saw anatomical relationships  4. selective breeding, pigeons, dogs, horses, crops traits could be passed on  5. animals always over populate b/c he read economist Thomas Malthus

The Galapagos Islands were of special interest to him because of their unique life forms found no where else  huge turtles, many finches, swimming lizards

QUESTION  Why were the animals on the islands slightly different than the animals on the mainland?  If an animal migrated to the island from the continent, what caused it to change (evolve)?

ANSWER  Different environmental pressures benefited or hurt the animals with particular features  (adaptations= an inherited feature that increases an organism's chance of surviving in an particular environment).

2 fundamental factors that determine evolutionary change:  ANCESTRY  and  ENVIRONMENT

DARWIN'S EXPLANATION  "Natural Selection" is the mechanism that allows some forms to survive and others to die out.  not a conscious force, as there is a struggle for resources some organisms die while others live to reproduce.

 1859 “On the Origin of species by means of Natural Selection”  sold out the first day

Evolution for DUMMIES  1. over population  2. constant struggle for resources  3. variation in the species  4. the best adapted to the environment survive  5. surviving organisms transmit variation to offspring

 ALFRED RUSSEL WALLACE ( ) Malay Archipelago had the same idea as Darwin in 1858 (equally credited but Darwin gave extensive evidence)

 The Darwin– Wallace Medal was issued by the Linnean society on the 50th anniversary of the reading of Darwin and Wallace's papers on natural selection.

 The HARDWARE or material of evolution is variation, mutation and overpopulation  The MECHANISM for evolution is Natural Selection  Theories also have a predictive component as shown in the slides at the after the homework answer keys.

Test Topics: Friday  Evolution vs. Creationism  Literal vs Figurative Language (interpretation of the Bible)  Darwin – voyage, life, ideas, book, natural selection  Labs – peppered moths, fossil lab (evidence vs. inference)  Text , worksheet  Bishop Usher, James Hutton, intro to evolution

Evidence of relatedness  Example: Transitional forms in the fossil record Hypothesis: If terrestrial vertebrates (tetrapods) evolved from lobe-finned fish (sarcopterygians), then there should be transitional forms that possess traits that are intermediate.

Previously identified transitional forms From Ahlberg and Clack, Nature 2006

General Methods  Scientists looked specifically for the transitional form of interest by sampling…  Appropriate habitats (stream system)  Appropriate geologic time (early Late Devonian = mya) From Daeschler et al.,

They found Tiktaalik roseae! From Ahlberg and Clack, Nature 2006 From Daeschler et al., Nature

From Shubin et al., Nature

Summary  The study of and the evidence for evolution clearly fits within the scientific framework.  We use current evolutionary theory to make and test hypotheses  There are many thousands of examples of evidence for evolution

What data from whole genome sequencing can tell us about evolution of humans

Example: the Evolutionary Hypothesis of Common Ancestry Chromosome Numbers in the great apes: 46 human (Homo)46 chimpanzee (Pan)48 gorilla (Gorilla)48 orangutan (Pogo)48 Testable prediction: If these organisms share a common ancestor, that ancestor had either 48 chromosomes (24 pairs) or 46 (23 pairs). Testable prediction: If these organisms share a common ancestor, that ancestor had either 48 chromosomes (24 pairs) or 46 (23 pairs).

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

“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: – ), 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 Hillier et al (2005) “Generation and Annotation of the DNA sequences of human chromosomes 2 and 4,” Nature 434: 724 – 731. Human Chromosome #2 shows the exact point at which this fusion took place Chr 2