Written exam Essay Example | Topics and Well Written Essays - 1500 words

Written exam - Essay Example A good example is where giraffes with short necks die after short shrubs die out, and after some generations all the giraffes will have long necks. Mutation is the mechanism whereby a DNA gene structure in a species changes with some units being deleted, inserted or re-arranged in such a way that it affects or alters subsequent generations. An example is an albinism genetic anomaly (Wool, 67). Cladogenesis is the evolution that is brought about by the splitting of a lineage. This is the separation of a gene pool into two or more gene pools. Anagenesis, which is also known as phyletic evolution, is that which occurs within a lineage. It is basically the collective changes that completely alter a species into a new species with different characteristics (Wool, 74). The phylogenetic tree that uses ‘prosimian vs. anthropoid’ is different from the cladogram, which differentiates ‘strepsirhine vs. haplorhine’, in that it shows the ancestors together with the degrees of relationship and the time that the taxa lived contrary to cladograms, which only show the degree of relationship and a hypothetical ancestor (Jurmain et al., 68) A good example of this is propithecus diadema, also known as diademed sifaka. It is found in Madagascar. Its adaptation for grooming is what makes it special from other lemurs. It has a toothcomb and a toilet claw in its second toe mainly for grooming. The white-headed capuchin, which is a new world monkey found in Central and South America, is in the family of platyrrhines. This type of capuchin is special in the fact that it is dominated by both an alpha female and an alpha male. The Zanzibar red colobus found in the main island of Zanzibar, Unguja, is a good example of primates in this clade. The males of the Zanzibar red colobus are very social and defend their group in unison and even groom each other between meals. The gibbons are among the most endangered primates on earth and they fall under this