In the list below name the most likely force or forces of change resulting in the
observed pattern or change to a population.
SCENARIO
(a)There are five unrelated species of morphologically similar ‘anteaters’ that have evolved
independently in different parts of the world.
(b)Sequences of two individual humans chosen at random from a population show a single
nucleotide polymorphism (SNP) about every 500-1000 base pairs. Most of these SNPs do not affect the translation of amino acids.
(c)Recent genetic monitoring of Maui’s dolphins off the west coast of Auckland identified a
small number of Hector’s dolphins in the population sample.
(d)Only male beaked whales have emergent teeth (in the form of tusks) and only males are
covered with scars from these tusks.
(e)HIV patients treated with powerful anti-retroviral drugs eventually show a rapid increase
in the frequency of resistant virus.
(f)A species of New Zealand land snail exists in two strikingly different color patterns and
individuals with an intermediate colour pattern suffer higher mortality.
(g)In sub-Saharan Africa, individuals with one sickle-cell anemia allele have a lower
mortality than individuals who have two sickle-cell alleles or no sickle-cell alleles.
(h)A non-toxic species of butterfly has come to resemble a toxic species when the two species are found in sympatry.
(i)An unrelated breeding pair of takahe (the rare New Zealand endemic bird) is translocated
to an island sanctuary. The pair is very successful at raising young and the colony grows over the first generation. During the second generation, however, the number of chicks that survive to fledging declines rapidly.
(j)Hybridization between two plant species results in individuals with the chromosomes of
both parental species. The hybrids are self-fertile but cannot backcross to the parental species. Over time the hybrids become abundance and show habitat
lization within the range of the parental species.
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