Card Set Information

2012-02-28 18:19:30


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  1. monophyletic
    includes all descendants of a single ancestor
  2. paraphyletic
    includes some but not all the descendants of a single ancestor
  3. polyphyletic
    includes descendants of two or more ancestors, both of which have descendants that are not included in the taxon
  4. Stem group
    extinct group of species early in evolutionary time
  5. Crown group
    species derived from a stem group with distinct derived traits
  6. homologous structures
    mammalian forelimb ex. wing of a bat or flipper of a whale, result of conergent evolution
  7. parallelism or parallel evolution
    homoplasy that occurs among closely related species, controlled by hox genes, birds of beaks curved to reach nectar
  8. hox genes
    regulatory genes that can turn off and on haplotypes, makes organism better adapted to environment
  9. evolutionary reversal
    loss of limbs, fish to tetrapod to snake loss of legs
  10. conservative characters
    a character that evolved slowly pentadactyly unlike body size which changes quickly
  11. mosaic evolution
    • different characters evolve at different rates within a lineage
    • juveniles different---> adults similar
  12. gradualism
    darwin stated that evolution is slow
  13. saltations
    sudden bursts of change
  14. heterochrony
    evolutionary change in the timing of devlopment in organisms within a clade
  15. complexity
    decrease , angiosersms evolved having flowers with many floral parts to flowers having fewer such parts
  16. evolutionary trends
    • changes of character is the same direction
    • angiospersm flowers in some lineages have evolved longer nectar spurs requiring hummingbirds to have longer beaks
  17. adaptive radiation
    divergent evolution of numerous related lineages within a realtively short time, no single tred , different adaptations for different environments, finches from sa changed and were found on another continent
  18. genome size
    just because organisms have evolved more recently doesnt mean rgar they have larger genomes
  19. endosymbionts
    have smaller genomes than there free living relatives , because many of their ancestral genes are no longer needed
  20. orthologous genes
    genes that diverged from a common ancestral gene during speciation
  21. paralogous genes
    genes that originated from a common ancestral gene duplication
  22. paralogous region
    large sections of duplicated genes
  23. polyploidy
    complete genome is duplicated, common in plants