Evolutionary Biology Final Exam Study Guide PDF

Tyler Alexander Evolutionary Biology Final Exam Study Guide **Evolution by Natural Selection** - Darwin's finches' speciation on islands - - Feeding ecology of finches - - Are the finches variable? - - Heritability -- the degree the offspring resembles parents - - -...

Tyler Alexander Evolutionary Biology Final Exam Study Guide **Evolution by Natural Selection** - Darwin's finches' speciation on islands - - Feeding ecology of finches - - Are the finches variable? - - Heritability -- the degree the offspring resembles parents - - - - - - - - - - - - - - - - - - - - Are survival and reproduction non-random? **Yes** - What can cause genetic correlation? - - **Speciation** - Evolutionary relationship of living things - - - - - How many species are there on earth? - - - Species are evolutionarily "independent" units - - Reproductive isolation - - - Morphospecies - - - - Morphospecies -- fossils - - - Phylogenetic species concept - - - - Phylogeny results from descent with modification - - - Molecular phylogeny - - - - - Phylogenetic criteria  - - - Biological species concept - - - Isolation - - - - - Gene flow (Eukaryotes) - - - Allopatric speciation - - - - - Geographical isolation - - Vicariance - - - Meiosis and the steps - Polyploidy can create immediate genetic isolation. - - - Polyploid speciation common in plants - - - - Chromosomal mutations can also lead to speciation - - Other mechanisms of isolation - - - Divergence - - - Natural selection and genetic drift - - Are these divergent phenotypes the result of evolution by natural selection?  - - - Assortative mating (Another way that populations can diverge in ways that promote speciation involves mating behavior) - - - - Hybridization and gene flow - - - - Pre- and post-zygotic isolation - - - - The geneticist Theodosius Dobzhansky (1937) reasoned that if populations have diverged during a period when the groups lived in different geographic areas, then any hybrid offspring that are produced should have markedly reduced fitness relative to individualsin each of the parental populations.  - - - - - - **Human embryonic development** - Two and four cell stage of the embryo can be separated and develop into individuals (identical twins, quadruplets) - Key points about the 8 cell stage embryo (2-3 days): - **Cell type:** The individual cells are called blastomeres.  - **Compaction:** A significant event happening at this stage where the blastomeres flatten and tightly connect to each other.  - **Embryonic genome activation:** This process, where the embryo\'s own genes start to be expressed, usually begins around the 8-cell stage.  - **Totipotency:** Each cell at this stage has the potential to develop into any cell type in the body, including the placenta.  - However, if you attempted to separate these egg cells the embryo would die. - Primordial germ cells have developed by the 2^nd^ week -- ovaries & testes - Medawar's theory - the force of natural selection remains high until the first reproduction - -