2Evolution Definition of Evolution the process by which species arise and change over time.The idea that all organisms have descended from common ancestors
3Evolution Charles Darwin Origin of Species, 1859 Decent with ModificationNatural SelectionSexual selection
4Evidence of Evolution Fossil Record Taxonomy Comparative Anatomy tells the story of evolutionTaxonomyClassifying organisms into groupsComparative AnatomyHomologous structuresIntermediate formsVestigial structuresComparative EmbryologyEarly embryos of vertebrates are alikeMolecular Biology –DNA, proteinsmtDNA
5FossilsAn organism becomes a fossil only if it dies under the right conditions.Majority of dead plants and animals are consumed by other organisms and leave no trace.Dead organisms only leave a trace or imprint if they are quickly buried in a bog or at the bottom of a lake/ocean.
6Clues of Human Evolution Paleontologists find fossils
7Clues of Human Evolution Remains of humans were preserved in fossils
8Bog is a wetland low in nutrients, slightly acidic soil . MossyTollund Man. (Denmark)Europe Iron age 2,400 ya
9Buried in mud or at the bottom of a body of water, the remains of the dead are protected from scavengers, erosion and decay.Become buried deeply in successive layers of mudOver time pressure from all these layers of sediment turns the deepest layers into sedimentary rockAfter millions of years geologic forces raise the rock into mountains, canyons and reveal fossils
10Sedimentary RockGrand Canyon showing layers of rock.
11TaxonomyAll organisms are grouped into hierarchies based on their relationships.Organisms of the same species can breed and produce viable offspringMajor taxonomic levels - KPCOFGS
12Taxonomy Common Name: Human Chimpanzee Lion Kingdom Animalia Phylum ChordataClassMammaliaOrderPrimatesCarnivoraFamilyHominidaeFelidaeGenusHomoPanPantheraSpeciessapienstroglodytesleo
13Taxon0my Binomial nomenclature Genus and species Homo sapiens. Homo means “self” or “same”, meaning “the same as me” — which, for you, means “human”. Sapiens means “wise”. Homo sapiens means “Wise human”.
14Comparative AnatomySpecies descended from a common ancestor may evolve in different directions and still keep some of the same characteristicsEvolutionary scientists compare the body structures of organisms to find clues.
15Comparative AnatomyHomologous Structures – similar structures in two or more species that give evidence of a common ancestor.Similar structureSame originDifferent in function
16Comparative AnatomyCompare legs of Human and Ape
17Comparative AnatomyIntermediate forms – successive changes in homologous bone structures provide evidence of evolution.Also called transitional forms
20Comparative Anatomy Vestigial Structures A part of an organism with little or no function that reflects evolutionary history
21Comparative Embryology Compare Embryo Development
22Molecular Biology DNA, mtDNA, proteins 20 -20,000 genes in the Human GenomeMolecular geneticists have compared DNA sequences of Humans and chimpanzees98.8% identicalHumans are more closely related to African apes than Asian apes (Immunological protein analysis)
24Mitochondrial DNA contains 37 genes Thirteen of these genes provide instructions for making enzymes involved in oxidative phosphorylation. Oxidative phosphorylation is a process that uses oxygen and simple sugars to create adenosine triphosphate (ATP), the cell's main energy source.The remaining genes provide instructions for making molecules called transfer RNA (tRNA) and ribosomal RNA (rRNA)
25Mitochondrial DNAPassed from mother to all her childrenPoints of mutations are a clear .
30Homework Look up Rift Valley Explain where it is Explain why it is important to the study of Human Evolution.
31Becoming Human As we have evolved Humans have Larger brains Walk bipedallySparse body hairNonopposable toes and longer feetGrasping flexible thumbUnspecialized teethArching backs
32Becoming Human Australopithucus afarensis Lucy Found in Ethiopia in 1974This the earliest species of Australopithecus, lived in about 4 million and 3 million years ago.brain was about the same size as chimps3 feet, 70 lbs
33Becoming HumanThe researchers also found that the model of locomotion produced in their simulations closely matched a set of fossilized footprints thought to have been left by A. afarensis in Laetoli, Tanzania, some 3.6 million years ago.
34Becoming HumanThey constructed the computer model using a fossilised A. afarensis skeleton known as "Lucy", recovered from Ethiopia in The researchers then added virtual muscle to their simulation and used genetic algorithms to "evolve" the optimal walking movement for the creature.
35Becoming Human Australopithicus africanus lived perhaps from 3 million to 1 million years ago, and probably evolved from A. afarensishad a rounder skull and slightly larger brainTooth and jaw design suggest he chewed plant foods, but might also have scavenged meat from the remains of carnivores' kills.
36Becoming HumanNeanderthal Man Fossils found in Germany
37Becoming Human Homo neanderthalensis More Neandertal skeletons have been found than any other ancient human species. They lived in Europe and Southwest Asia from at least 130, ,000 years ago.May have evolved from Homo heidelbergensis in Southern Europe.
38Becoming Human protruding jaw, receding forehead, and weak chin. The average Neanderthal brain was slightly larger than that of modern humans, but this is probably correlated with larger body size in general.May have been a different species than Homo sapiens.
39Homo heidelbergensis (600,000 to 100,000 years ago) The skulls of this species share features with modern Homo sapiens.brain was smaller than most modern humans
40Becoming Human Homo sapiens sapiens Cro magnum man Earliest modern man Lived 35,000 yaThe body heavy and solid , muscular.Straight forehead with slight browridgesCro-Magnons were the first humans to have a prominent chin.
42Comparison of erectus, aferensis, neanderthal An evolutionary comparison (from left to right: Homo erectus, 1 million years old; Australopithecus afarensis, 2.5 million years old; Homo neanderthalensis, 100,000 – 32,000 years old)