Evolutionary biologists have long held the view that most new species arise as a result of adaptation to various environments. However, a recent study from the University of Toronto suggests otherwise.
The research, which was reported in the journal Science, fills in a knowledge gap that scientists have dubbed a "blind spot" in our comprehension of how and why new species emerge.
Most species evolve by adaptation
Sean Anderson, who co-authored the paper with Professor Jason Weir while pursuing his Ph.D. at the University of Toronto Scarborough, says that "we found species are actually consistently adapting to similar environmental pressures."
Although they're not adapting in drastically different environments, they are going through classic Darwinian evolution.
Although it's generally accepted that populations need to be physically separated in order to start evolving into new species, scientists say it's unclear what happens during that isolation.
Ecological speciation has been the prevailing theory for many years.
According to this theory, groups evolve as a result of migration to new environments and encountering pressures that the rest of their species do not, such as predators or new food sources.
The natural selection that results in the emergence of a new species is then called divergent adaptation.
One illustration is Darwin's finches, which evolved beaks that were better suited for seeds than they were for insects.
However, it is also common to see species that have developed to the point where they are no longer able to breed with their closest relatives but still exhibit the majority of the same characteristics.
This led scientists to suspect that, despite being geographically remote, the environments in which evolution occurred may not have been as distinct.
Parallel adaptation is a well-known but less popular explanation.
The researchers used the biggest and most comprehensive collection of sister pairs, or closely related species, of divergent traits, ever put together.
Additionally, they developed a statistical model that can now be used to calculate whether a species evolved through parallel or divergent adaptation.
Nearly 3,000 sister pairs of birds, mammals, and amphibians revealed that most of their species underwent comparable intense environmental pressures during their evolution.
According to Anderson, who is currently completing post-doctoral research at the University of North Carolina at Chapel Hill, "We found this really consistent signature where parallel adaptation seems to be what dominates and it doesn't matter what traits you look at, it's the same in just about every group of species pairs you've got." We were taken aback by how reliable this signature was.
According to Anderson, species may occasionally be evolving similar traits while going through genetic changes. They might evolve into a different species as a result.
The findings may have wide-ranging effects because biologists can infer information about biodiversity from theories about how species evolve.
Building biodiversity necessitates diverse habitats with various resources and difficulties since the majority of species evolve through divergent adaptation.
Biodiversity, however, is dependent on both time and geographic distance if parallel adaptation is taking place.
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How are living things adapted to their environments
Living things adjust to their surroundings. This indicates that they are adapted to survive and reproduce in their habitats due to the way they appear, behave, are built, or live, as per American GeoSciences Institue.
For instance, giraffes have extremely long necks that enable them to consume tall vegetation that is out of reach for other animals.
Cats have eyes that resemble slits. The cat's eyes can thus adapt to both bright light when the slits are narrow and to very dim light when the slits are wide open.
A crucial adaptation is behavior. Animals pass along a variety of adaptive behaviors. Meerkats, a small species that inhabits southern Africa and resides in sizable colonies.
The meerkats alternately stand on their hind legs and scan the sky for raptors. The remaining meerkats in the colony go about their daily lives in the meantime.
There are probably a lot more physical or behavioral traits that animals have that make their lives easier.
A crucial adaptation is behavior. Animals pass along a variety of adaptive behaviors. Meerkats, a small species that inhabits southern Africa and resides in sizable colonies.
The meerkats alternately stand on their hind legs and scan the sky for raptors. The remaining meerkats in the colony go about their daily lives in the meantime.
There are probably a lot more physical or behavioral traits that animals have that make their lives easier.
In biology, a species' overall place in its environment is referred to as its ecological niche. There are many niches in most environments.
A new species is likely to evolve to occupy a niche if it is "empty" (i.e., not occupied by any organisms). Natural selection is the process that results in this.
Natural selection causes a species' nature to gradually change so that it can fit into the niche.
A species can persist for a very long time before going extinct if it becomes extremely well adapted to its environment and if the environment does not change.
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