BIOL 1202 Chapter : Learning Objectives Chp 26
Document Summary
Chapter 26: phylogeny and the tree of life. A closer examination reveals that bat wings are far more similar to the forelimbs of cats and other mammals than to a bird"s wing. Bats and birds descended from a common tetrapod ancestor that lived about 320million years ago. Thus, although the underlying skeletal system of bats and birds are homologous, their wings are not. Fossil evidence documents that bat wings and bird wings arose independently from the forelimbs of different tetrapod ancestors. Thus, with respect to flight, a bat"s wing is analogous, not homologous, to a bird"s wing: define molecular systematics. Explain some of the problems that systematists may face in carrying out molecular comparisons of nucleic acids: molecular systematics: a scientific discipline that uses nucleic acids or other molecules to infer evolutionary relationships between different species. Concept 26. 3: shared characters are used to construct phylogenetic trees: cladistics, cladogram: a diagram depicting patterns of shared characteristics among species, define a clade.
