Question

Which of the following statements about adaptive radiation is correct? a. Adaptive radiation occurs very slowly over time. b. Adaptive radiation occurs within a single lineage. c. Adaptive radiation occurs in the presence of competitors. d. Adaptive radiation occurs in species that live in one habitat.

Answer 1

Adaptive radiation refers to the rapid diversification of a single lineage into multiple species, each adapted to different ecological niches, typically in geographically isolated environments such as island archipelagos. An example of adaptive radiation is the diversification of the Hawaiian honeycreeper from a single species.

Step-by-step explanation:

Among the statements about adaptive radiation, the correct one is that adaptive radiation occurs within a single lineage. Adaptive radiation typically happens when a single species diversifies into several distinct species, each adapted to a unique niche or isolated habitat. This process can happen relatively quickly, especially in areas where geographical isolation occurs, such as island archipelagos. The Hawaiian honeycreeper is an exemplary case of adaptive radiation, where multiple distinct species evolved from one founder species due to the diverse ecological niches available across the Hawaiian Islands. Selective pressures and isolation lead to a burst of speciation originating from a common ancestor, which characterizes adaptive radiation. This is in contrast to gradual speciation, where species diverge slowly over time, or in the presence of competitors, which can lead to convergent evolution rather than adaptive radiation.

Answer 2

c. Adaptive radiation occurs in the presence of competitors.

Step-by-step explanation:

Adaptive radiation is a process of diversification in which new species are originated from an ancestral species due to changes in the enviroment or deu to pressures such as competition for resources that lead organisms to find new niches. For example, if there are many competitors for the same food source, that pressure could lead some organisms to look for a new food source, that, in turn, can lead to the adaptation of their body to the new food source. For example, bird beaks that were specialized for seeds can be adapted for insects.