Question

Use the information below to answer questions A - C. You are studying a population of kangaroos. These kangaroos only exist on one island in the Pacific Ocean. Imagine that coat color (brown or white) is highly heritable while fur density (thin or thick fur) is not heritable. When you begin your study, 90% of the kangaroos are brown (and half of these kangaroos have thin fur). The other 10% are white (and half of these have thin fur). Several generations later you discover that 60% of the kangaroos have brown fur (and half of these have thin fur). The other 40% are white (and half of these have thin fur).

A. Has this population evolved? Circle simply YES or NO

B. Define biological evolution and then, using the information presented in the example above, explain your YES or NO answer. (3)

C. Use the information above to explain the difference between highly heritable and non-heritable traits.

Answer 1

A)Yes the population is evolving,as the allele frequencies changes from one generation to another.Individuals with high favourable variation or phenotype survive and breed to produce more young ones,thus evolution of population with different trait hsppens.

B) Biological evolution-It occurs when genetic and inherited trait if biological population undergo modification from parents to the offspring and then to another generation.It can take place in on a micro scale or in macro scale across the populations.Such change in gene frequency results in survival of fittest.Genetic druft,allopatric speciation and natural selection can also leads to evution in a particular population.In the example given above,the brown thin fured kangaroo polutaion which was high in number at the initial stage compared with white thick fured kangaroos.After several generation the light thin fured trait was found high in number compared with brown thin fur.The change in frequency of a gene which is specific for lighter colour thin fur appears larger number in the population resulting in evolution.Change in environment condition favoured the lighter colored trait with thin fur to adapt well and produce successful offspring.

C) Heritable and Nan heritable trait

Heritable characteristics of an individual is passed on to the next generation during sexual reproduction by genetic material.eg-eye colored ,skin colour,

In present example coat colored is heritable.

Non heritable characteristics of an individual is not passed on to one generation to next generation as those traits are acquired.

The fur density of the kangaroo population is not heritable,which depends on environmental factors.