A textbook example is Darwin finches from Galapagos, whose ancestor colonized a competitors-free archipelago and rapidly radiated in 13 species, each one adapted to use the food resources in a different way.
This and other examples have led some to think that the progenitors of the major evolutionary radiations are those that happened to be in the right place and at the right time to take advantage of ecological opportunities. However, is it possible that biological diversification not only depends on the properties of the environment an ancestral species finds itself in, but also on the features of the species itself?
Now a study supports this possibility, suggesting that possessing a large brain might have facilitated the evolutionary diversification of some avian lineages.
Over 20 years ago, Jeff Wyles, Allan Wilson, and Joseph Kunkel proposed that big brains might favor adaptive evolutionary diversification in animals by facilitating the behavioral changes needed to use new resources or environments, a theory known as the behavioral drive hypothesis. When these authors formulated their hypothesis, evidence that the size of the brain limits the cognitive capacity of animals were scanty.
Since then, however, a substantial body of evidence has confirmed that animals with larger brains, relative to their body size, have more developed skills for changing their behavior through learning and innovation, facilitating the invasion of novel environments and the use of novel resources. Despite the progress, the role of the brain in the adaptive diversification of animals has remained controversial, mostly due to the difficulties to demonstrate that big-brained animals evolve faster. Now, ecologist Daniel Sol of CREAF-Autonomous University of Barcelona and evolutionary biologist Trevor Price of the University of Chicago, provide evidence for such a role in birds in an article in the August issue of The American Naturalist.
Analyzing body size measures of 7,209 species (representing 75% of all avian species), they found that avian families that have experienced the greatest diversification in body size tend to be those with brains larger than expected for their body size. These include the Picidae (woodpeckers), Bucerotidae (hornbills), Psittacidae (parrots), Strigidae (owls), Menuridae (lyrebirds) and Corvidae (crows). Brain size can promote morphological diversification because it facilitates range expansions and speciation, yet the analyses indicate that the brain-diversification association is statistically independent of geographic range and species richness.
"The most likely alternative," Daniel Sol states, "is that big brains enhance the rate of evolutionary diversification by facilitating changes in behavior, which would place new selection pressures on populations and favor adaptive divergence." Thus, in species with high cognitive styles, behavior might be, along with environmental factors, a major driving force for evolution.
Patricia Morse | EurekAlert!
New eDNA technology used to quickly assess coral reefs
18.04.2019 | University of Hawaii at Manoa
New automated biological-sample analysis systems to accelerate disease detection
18.04.2019 | Polytechnique Montréal
A stellar flare 10 times more powerful than anything seen on our sun has burst from an ultracool star almost the same size as Jupiter
A localization phenomenon boosts the accuracy of solving quantum many-body problems with quantum computers which are otherwise challenging for conventional computers. This brings such digital quantum simulation within reach on quantum devices available today.
Quantum computers promise to solve certain computational problems exponentially faster than any classical machine. “A particularly promising application is the...
The technology could revolutionize how information travels through data centers and artificial intelligence networks
Engineers at the University of California, Berkeley have built a new photonic switch that can control the direction of light passing through optical fibers...
Physicists observe how electron-hole pairs drift apart at ultrafast speed, but still remain strongly bound.
Modern electronics relies on ultrafast charge motion on ever shorter length scales. Physicists from Regensburg and Gothenburg have now succeeded in resolving a...
Engineers create novel optical devices, including a moth eye-inspired omnidirectional microwave antenna
A team of engineers at Tufts University has developed a series of 3D printed metamaterials with unique microwave or optical properties that go beyond what is...
17.04.2019 | Event News
15.04.2019 | Event News
09.04.2019 | Event News
18.04.2019 | Life Sciences
18.04.2019 | Physics and Astronomy
18.04.2019 | Life Sciences