Chapter 10, Problem 28P

A small population of deer living on an isolated island are separated for many generations from a mainland deer population. The populations retain the same number of chromosomes and but hybrids are infertile. One chromosome (shown here) has a different banding pattern in the island population than in the mainland population.

Describe how the banding pattern of the island population chromosome most likely evolved from the main-land chromosome. What term or terms describe the difference between these chromosomes?

Draw the synapsis of these homologs during prophase I in hybrids produced from the cross of mainland with island deer.

In a mainland–island hybrid deer, recombination takes place in band $\text{q1}$ of the homologous chromosomes. Draw the gametes that result from this event.

Suppose that $40\%$ of all meioses in $\text{mainland–island}$ hybrids involve recombination somewhere in the chromosome region between $\text{q2}\text{.1}$ and $\text{p2}$. What proportion of the gametes of hybrid deer are viable? What is the cause of the decreased proportion of viable gametes in hybrids relative to the parental populations?