Three allopatric species of cat native to Israel are also highly sexually dimorphic, resulting in six unique morphotypes. Each of these has teeth whose size distributions overlap very little where species co-occur, but are much more variable where no other species occur. The most plausible hypothesis to explain this pattern is: a. community wide character displacement has acted to reduce competition for limiting prey.
b. the cats are incorrectly identified and must belong to the weasel family, Mustelidae.
c. teeth are phylogenetically conservative and subject to environmental filtering.
d. teeth are used as a signaling device within species to identify potential mates.
e. the cats are involved in an evolutionary arms race towards larger teeth.

Approximately 90% of all cases of polycystic kidney disease are inherited in an autosomal dominant fashion. the disease is typically related to mutations to genes (pkd1 and pkd2). pkd genes can be found on chromosome 16. the disease occurs in approximately 1: 800 to 1: 1000 people. here is a hypothetical example. the dominant allele d will cause the development of pkd. the recessive allele is known as d. what genotypes would correspond to suffering from pkd? dd, dd what genotypes would correspond to being normal (not suffering from pkd)? dd consider that 1: 1,000 people have pkd in your population of 325million. consider that pkd is inherited in an autosomal dominant fashion. show you math for all of the following questions: what is the genotypic frequency for dd? what is the genotypic frequency for dd? what is the genotypic frequency for dd? what is p? what is q? how many people in your population would have pkd?

Examine the two squirrel populations in the accompanying figure. the populations are separated by a geographic barrier. if after a long period of time the two species are no longer separated, what evidence is needed to determine if speciation has occurred? the figure shows two populations of squirrels separated by a geographic barrier. examine the two squirrel populations in the accompanying figure. the populations are separated by a geographic barrier. if after a long period of time the two species are no longer separated, what evidence is needed to determine if speciation has occurred? the figure shows two populations of squirrels separated by a geographic barrier. polyploidy is creating new species. the two populations are not interbreeding freely. hybrid offspring of the two populations begin to appear. one species will increase into a population size twice as large as the other species.

New york city has 2,181 inhabitants per square mile. the state of alaska has 1.03 inhabitants per square mile. ecologists would say alaska has a low exponential growth population density birth rate carrying capacity