Micro- vs. macroevolution Overview of the Kingdom animalia

1. Micro- vs. macroevolutionOverview of theKingdom animalia BIOL240.002 Zoology 27 August 2014

2. Micro- vs. macroevolution

3. Species Concepts • Typological—Outdated belief that a species had an “essence” its members expressed to varying degrees • Biological—Recognize separate species based on whether or not they interbreed • Morphological—Use morphological distinctiveness to determine whether or not groups are interbreeding • Evolutionary—Separate species have their own separate evolutionary fates and tendencies • These days, almost always analyzed with inclusion of analyses assessing genetic divergence

4. Microevolution • Population: Members of a species sharing time and space • Population Gene Pool: All the genetic variants (alleles) among the individuals of a population • A change in population allele frequencies over time, due to • Genetic Mutation • Natural Selection • Genetic Drift • Gene Flow (Dispersal) • Non-random Mating

5. Genetic Mutation • DNA  RNA  Protein • [Gene] [Enzyme, etc.] • ACTG nucleotide sequence  Amino acid sequence • Mutation is an accidental change in the ACGT sequence • Generally harmful • Selected against • Sometimes neutral • Selectively neutral • Very rarely, beneficial to survival and reproduction • Selected for

6. Modes of Natural Selection Fig. 1.32 p. 32

7. Peppered Moth (Bistonbetularia) Melanism • Melanistic version initially very rare, but became common in late 1800s/early 1900s • Bernard Kettlewell, 1950s • Released both variants near industrial Birmingham and in Dorset countryside • Birmingham: Higher recapture rate for melanistic morph • Dorset: Higher recapture rate for peppered morph Fig. 1.27 p. 26

8. HANDOUT—Kettlewell’s Data

9. Melanistic Moths and Air Pollution Abatement Fig. 1.27 p. 26

10. HANDOUT—Majerus’ Experiments

11. Genetic Drift • Chance change in allele frequencies • More likely in small populations • Bottleneck: Few survivors of catastrophic mortality event • Founders’ Effect: Few individuals disperse beyond a barrier and establish a new population

12. Nonrandom Mating • Individuals may choose mates based on certain phenotypes

13. Gene Flow • Dispersal among populations • Spreads beneficial mutations • The more gene flow, the more genetically homogenized populations are • The less gene flow, the more genetically divergent they become

14. Allopatric Speciation • “Allo” = different • “patry” = fatherland • Separation of populations via any barrier to gene flow • Separate selective regimes • Mutations arise independently in either group of populations • Genetic drift • Esp. if few in number on one side of the barrier • Over time, genetic divergence • If re-contact occurs, may or may not still be able to interbreed

15. Eucidaris Sea Urchins Fig. 1.20 p. 22

16. Ensatinaeschscholtzii Salamanders Fig. 1.21 p. 23

17. Mass Extinctions Fig. 1.34 p. 34

18. Overview of the Kingdom animalia

19. Symmetry Fig. 3.1 p. 60

20. Embryonic Development • Morula: Solid mass of cells • Blastula: Fluid-filled single layer of cells • Gastrula: Embryo developing its digestive tract Fig. 3.9 p. 67

21. Radial vs. Spiral Cleavage Fig. 3.3 p. 61

22. Ectoderm, Mesoderm, and Endoderm • Ectoderm: Outermost layer of cells • Becomes the integument • Endoderm: Inner layer of cells • Becomes the digestive tract • Mesoderm: In-between layer • Produces muscles, connective tissues, and circulatory, excretory, and reproductive systems

23. Body Cavities Fig. 3.5 p. 63

24. Body Cavities Fig. 3.10 p. 67

25. Protostomes vs. Deuterostomes Fig. 3.8 p. 66

26. Protostomes vs. Deuterostomes Fig. 4.10 p. 91