Charles Darwin (1809-1882), In 1831, Charles Darwin sailed to the Galapagos Islands in the HMS Beagle. “Father of Evolution” Natural Selection
Alexander Oparin proposed that life began in the early oceans where a rich "primordial soup" of chemical compounds could build up. He suggested that energy from UV light and lightening could form these compounds.
Miller-Urey Experiment Voltage Ammonia + nitrogen + methane + hydrogen + water + Voltage …after some time amino acids and organic compounds (BUT NOT LIFE) VIDEO of Miller Explaining the Experiment http://www.ucsd.tv/miller- urey/miller1.mpg
James Hutton: The Father of Modern Geology The earth had to be much more than a few thousand years old (6,000) and more like millions. (ie., lava pushed up land for volcanoes)
Charles Lyell Principles of Geology The processes that occurred in the earth in the past still occur today.
Accepted Age of the Earth 4.5 - 4.6 billion years old LIFE AROSE 3.5 billion years ago
Lamarck (1744 -1829) theory of inheritance of acquired characteristics FALSE
Then according to Lamarck… Pass on longer necks. Or if you lift weights, your children will be big-muscled! BUT…
So…Lamarck was wrong! Passed-on-traits must be in the chromosomes in the sex cells
Malthus 1766-1834 Population would outrun food supply, leading to a decrease in food per person.
Darwin’s 5 Year Journey Darwin observed and collected thousands of wildlife specimen he had never before encountered.
Galapagos Islands Galapagos islands Stock Footage and Video Clips. 39 Galapagos islands videos and movies available to search from over 20 royalty free motion brands.Galapagos islands Stock Footage and Video Clips. 39 Galapagos islands videos and movies available to search from over 20 royalty free motion brands. H.M.S. Beagle
Does Natural Selection depend On genotype or phenotype? PHENOTYPE
VIDEO Evolution: How Does Evolution Really Work? Click on Video for StudentsEvolution: How Does Evolution Really Work?
Fitness Ability of an organism to survive and reproduce in its specific environment DESERT: Sleep in cool dens
Adaptations Inherited characteristics that increases an organisms chance to survive Big ears dissipate heat Leafcutter carries 50x’s its weight
Western Grebe Courtship Western Grebe Courtship Movie In the “rushing” display, the mating pair swim side-by-side with their wings held back, their long necks arched, and their yellow beaks angled upward.
theory of universal common descent = all organisms on earth are descended from a common ancestor.
Darwin thought the Galapagos finches descended from finches of what country? Ecuador
We are more different than thought! Previous estimates of genetic similarity between humans and chimpanzees suggested they were 98.5–99% identical. However, after the sequencing of the chimpanzee genome 2005, the DNA similarity was fixed at 96%. Nature, the Chimpanzee Sequencing and Analysis Consortium, which is supported in part by the National Human Genome Research Institute (NHGRI), one of the National Institutes of Health (NIH),
Factors Affecting Natural Selection Food supply Disease Unable to mate Weather natural selection Fitness of organisms
Where to find fossils? Most fossils are found in sedimentary rock. Examples of sedimentary rock are limestone, shale, and sandstone.
Historical Record of Organisms Youngest (on top) mammals/birds Nextreptiles Nextamphibians Nextfish Oldest (on bottom)prokaryotes
Assume that Sedimentary rock is laid down with the oldest rock layer on the bottom and the youngest rock layer on the top
Which is the most probable assumption about species A, B, and C ( In undisturbed rock layers)? 1. Species B is more abundant than species C. 2. Species C existed before species B. 3. Species A and B are genetically identical. 4. Species B descended from species A.
When the industrial revolution arrived in England, the pollution had turned the bark of the trees a much darker color. Since light colored moths are much easier for birds to see on a dark background, they were preferentially eaten.
Some say this is not true! 1. Moths fly at night (so color would not be a factor). 2. Moths don’t land on tree trunks; they hang on upper canopy tree limbs.
Sexual Dimorphism Secondary sexual characteristics: color, size, etc. different in males and females
Main Ideas of Darwin 2. descent with modification See “gradualism” and “punctuated equilibrium”
Descent with Modification: Hawaii honeycreepers
So…descent with modification Evolution is a remodeling process Do you agree?
Darwin’s Ideas (cont.) 3. Living species have arisen from earlier life- forms (common descent)
Common Descent Theories Phyletic GradualismPunctuated Equilibrium
Phyletic Gradualism Gradual changes You would see transitional fossils (in-between forms)
Lucy: Man or Ape? Adult female - 25 yrs About 40% of her skeleton found Her pelvis, femur (the upper leg bone) and tibia show her to have been bipedal. About 107 cm (3'6") tall (small for her species) About 28 kg (62 lbs) in weight.
Where did Lucy get her name? When the bones were found, the Beatles' song "Lucy in the Sky With Diamonds" was playing over during a night of dancing and drinking.
Dr. Donald Johanson recollects "I happened to glance over my right shoulder...and there on the surface of the ground was a little bit of an elbow, I recognized it immediately as belonging to a human ancestor.” (good eyes?) November 30, 1974, in Hadar, Ethiopia.
Not A Human Arguments Lucy’s DNA found she was indeed an ape (Cell magazine) - few skeletal bones which were usually fragmentary and often poorly preserved. - bones found far apart (1.5 miles away)
Other questions on Lucy Present day orangutan and spider monkeys have the same angle (pelvic and knees) as humans yet are extremely adept tree climbers.
And... Her brain size is still small, ape- like in proportion The jaw, in particular, is distinct in that it is V-shaped, totally unlike human jaws.
Population Group of individuals of the same species living in the same place at the same time.
What is... The smallest unit that can evolve? population
Molecular Biology Homologies : Similarities in blood, proteins and DNA and RNA sequences that indicate species relatedness; the greater the similarities, the more closely related two organisms are thought to be
Comparative Molecular Biology: Number of Amino Acid Differences with humans Human 0 Gorilla 1 Gibbon 2 Rhesus monkey 8 Dog 15 Horse, cow 25 Mouse 27 So organisms with similar DNA or proteins would be more closely related
Darwinian Fitness Contribution an individual makes to the gene pool of the next generation relative to the contribution of other individuals
Gene Pool The total collection of all genes in a population at one time.
Contrast Microevolution Changes within a species EXAMPLE: humans are getting taller Macroevolution Species change into other species EXAMPLE: reptile into a bird
Microevolution Darwin did in fact observe small changes, such as changes in the size and shape of finch beaks etc.
Macroevolution? Darwin never did see a finch turn into an iguana or visa versa (or any other such major change). Major changes are theorized to take millions of years.