adaptive radiation process by which a single species evolves into many new species to fill available niches; this often occurs after a mass extinction.

Adaptive radiations are common after mass extinctions, which leave a bunch of empty niches just waiting to be filled by new species. There may be many unoccupied niches just waiting for species to fill them, but the organisms require a specific feature or characteristic in order to take advantage of them.

Adaptive radiations occur after mass extinctions because adaptive radiations are periods of evolutionary change in which groups of organisms form many new species whose adaptations allow them to fill different ecological roles, or niches, in their communities that often follow mass extinction events.

20 million years

In fact, many classic examples of adaptive radiations involve islands or lakes; notable examples include Darwin’s finches of the Galapagos, honeycreeper birds and silversword plants of Hawaii, and cichlid fish of lakes Malawi and Victoria in Africa.

lampreys. What is the main reason that mammals underwent adaptive radiation after the demise of the dinosaurs? A. They had to adapt in order to physically survive the ice age.

The occurrence of the phenomena of adaptive radiation is the result of natural selection, artificial selection, sexual selection, mutation pressure, genetic drift, or migration. It indicates evolutionary variations that are quite adaptive to a specific environment.

However, the two concepts differ in a way that adaptive radiation deals more with small-scale evolution over a shorter span of time whereas divergent evolution looks through the evolution of species diverging from its ancestors over a relatively long span of time.

In evolutionary biology, adaptive radiation is a process in which organisms diversify rapidly from an ancestral species into a multitude of new forms, particularly when a change in the environment makes new resources available, alters biotic interactions or opens new environmental niches.

Adaptive radiation is a rapid increase in the number of species with a common ancestor, characterized by great ecological and morphological diversity. The driving force behind it is the adaptation of organisms to new ecological contexts.

Adaptive radiation refers to rapid evolution of various different species from a common parent species. It leads to speciation. Adaptive radiation is caused when there is an ecological opportunity or availability of a new adaptive zone to explore.

Human evolution is not adaptive radiation. This is because adaptive radiation is described as the diversification of ancestral lines into different forms.

HENRY FAIRFIELD ()SBORN

Darwin’s finches are a classic example of adaptive radiation. The ecological diversity of the Galápagos in part explains that radiation, but the fact that other founder species did not radiate suggests that other factors are also important.

These six distinct forms, also called ecomorphs, are so consistent on each island that they’ve been sorted into specific categories (see image above). This is also an example of convergent evolution since the various ecomorphs each evolved independently on different islands.

Natural selection only acts on the population’s heritable traits: selecting for beneficial alleles and, thus, increasing their frequency in the population, while selecting against deleterious alleles and, thereby, decreasing their frequency. This process is known as adaptive evolution.

Darwin’s finches are a classical example of an adaptive radiation. Changes in the size and form of the beak have enabled different species to utilize different food resources such as insects, seeds, nectar from cactus flowers as well as blood from iguanas, all driven by Darwinian selection.

The mechanism of adaptive radiation helps explain this diversity. An adaptive radiation is a burst of evolution, creating several new species out of a single parent species.

Adaptive radiation describes the rapid evolutionary diversification of a single ancestral line. It occurs when members of a single species occupy a variety of distinct niches with different environmental conditions.