The answer is invasive species.
Invasive species are species that are not native to specific ecosystem,
but they have a capability to spread widely through the ecosystem, This way
they can threaten native species of the ecosystem or cause
environmental harm.
<span>After being introduced into the Black Sea, they greatly affect local
ecosystem. In the new area, they have no natural predators and are able to
spread. If they spread beyond the area they are introduced, they
become invasive species which can overgrow native biotopes and are
a great threat to the local biodiversity. This could lead to the extinction
of some native species.</span>
Answer:
When resources are limited
Explanation:
Answer:
directional selection
Explanation:
The directional selection is a type of Darwinian selection where a particular phenotype is favored in the population, thereby modifying the allelic frequencies to increase the proportion of the favored phenotype. <em>Biston betularia</em>, also known as peppered moth, is a species that was influenced by directional selection in its recent past. Before the industrial revolution, the frequency of light-colored moths was predominant compared to the darker-colored phenotypes, because this color has higher adaptive fitness in a clean, no pollution environment, thereby light-colored moths were able to avoid predatory birds. However, during the industrial revolution, the frequency of dark-colored moths increased in response to pollution (i.e. darker environment), thereby conferring a higher adaptive fitness to darker phenotypes.