MCAT Biology › Evolution
Vertebrates are evolutionarily adapted to terrestial life. Which one of the following adaptations is LEAST likely to contribute to this land-based predominance?
Vertebrates are evolutionarily adapted to terrestial life. Which one of the following adaptations is LEAST likely to contribute to this land-based predominance?
What is the definition of "fitness" in terms of evolution?
What is the definition of "fitness" in terms of evolution?
Inbreeding reduces the fitness of a population. This is the result of which increased genetic effect of inbreeding?
Inbreeding reduces the fitness of a population. This is the result of which increased genetic effect of inbreeding?
In a certain species of feline, all males are much larger than females. Members of either sex that are of intermediate size struggle to find mates. What principle best describes this phenomenon?
Which of the following is an example of natural selection?
I. Horses are bred for strength and endurance, and over time, the population of horses is more robust.
II. A late spring storm kills all the young plants in a region, but they are spared outside the storm zone.
III. Ancient ancestors of giraffes instinctively wanted to have longer necks to reach food higher in the trees, leading to the present appearance of giraffes.
IV. A flower that happens to be more attractive to pollinators is more likely to have reproductive success.
V. A mutation of a bacterium caused by exposure to ultraviolet light causes the originally red colonies to be yellow instead.
In a certain species of feline, all males are much larger than females. Members of either sex that are of intermediate size struggle to find mates. What principle best describes this phenomenon?
Members of a species of red fox have teeth of varying sharpness. Foxes with very sharp teeth are able to kill large prey for food, while foxes with very dull, strong teeth are able to crush eggs and small animals. Foxes with teeth of medium sharpness, however, cannot get food and many die before they are able to reproduce. Over time, the fox population shows a greater proportion of individuals with either very sharp or very dull teeth. Which type of natural selection best describes this situation?