The graph below shows the change in the frequency of allele…

The graph below shows the change in the frequency of allele A1 over 100 generations in four populations of fish. All four populations are found in separate, remote lakes and are completely isolated from each other, as well as, other populations.  The allele A1 does not affect the fitness of individuals who carry the allele, all changes in the frequency of allele A1, therefore, can be attributed to genetic drift. Given this information, which of the four populations is most likely the smallest?

A study on blood sharing among vampire bats has shown that a…

A study on blood sharing among vampire bats has shown that a hungry bat is more likely to receive a blood meal from another unrelated individual if the hungry bat has fed that same individual in the recent past. This observation supports the hypothesis that sharing of blood meals could have evolved by way of…

You perform an experiment to test for the evolution of resis…

You perform an experiment to test for the evolution of resistance in Salmonella bacteria to the antibiotic amoxicillin. To quantify the evolution of resistance in the population, you measure the “zone of inhibition” (i.e., how close the bacteria can grow to the antibiotic on the paper disk in the center of the Petri dish). After several generations, you find that the “zone of inhibition” has decreased in size—the bacteria are able to grow closer to the antibiotic paper disk. Based on these results, you can conclude…  

There are 500 toads in the population. Within this populatio…

There are 500 toads in the population. Within this population, coloration is determined by one gene with two alleles, a brown allele (B) and a yellow allele (b). The brown allele is dominant to the yellow allele. There are 350 toads that are brown. Assume the population is in Hardy-Weinberg equilibrium. Given this information, the frequency of the b allele is approximately and you would expect toads to be heterozygous (Bb).  

This phylogenetic tree depicts the evolutionary relationship…

This phylogenetic tree depicts the evolutionary relationships of eight major vertebrate classes.  Tiktaalik is an intermediate fossil that represents an early ancestor of all tetrapods. Specifically, Tiktaalik is known for its wrist, a key feature of the tetrapod limb that made it possible for which major evolutionary transition in animals? If you were to add Tiktaalik to this phylogeny, where would the Tiktaalik branch extend from?

Australian Marsupials have been geographically isolated from…

Australian Marsupials have been geographically isolated from Placental mammals for ~50 million years. In that time, many species in both groups have independently evolved the same adaptations via convergent evolution. The analogous adaptations observed in Placental mammals and Marsupials are best explained by…