Ravens are considered a dominant symbol around the world, including as a sacred animal in Aboriginal culture and as a harbinger of death in ancient Greece. Birds have played a prominent role in several cultures due to their widespread presence – about 40 species occupy Europe, Africa, Asia, Australia, and North and Central America. Now, a new study from Washington University in St. Louis, published April 21 in the journal Nature Communication, finds that there are good reasons to believe in the power of crows and their crow relatives, aside from their spiritual significance. 1
Evolutionary biologist Joan Garcia-Porta’s team found that ravens and ravens, both of the family Corvidae, were expanding their range and rapidly evolving into various species. After roaming most of the globe 22 to 18 million years ago, crows and ravens were exposed to new environments. To survive in these different niches, members of the genus Corvus experienced high rates of adaptation and species diversification around 10 million years ago. How the birds were able to do this, however, was a central question in the study.
Crows and ravens are renowned for their unique skills. Studies have shown that crows have cognitive abilities similar to adult apes and can mimic human speech. Meanwhile, crows are happiest when they use tools and are able to recognize human faces. But Garcia-Porta’s study focused on the physical adaptations that allowed corvids to disperse and diversify better than other birds, including elongated wings and large bodies that proved advantageous when they compete for resources with other avian species.
[Related: Why are crows and ravens such jerks?]
After establishing factors contributing to the geographic spread, the researchers analyzed the individual characteristics of 46 species of ravens and ravens to examine their physical diversity. The team used modeling software to unravel the genes and traits behind beak size, brain volume and femur length, among other variables. The results showed that the highest rates of diversification in crows and ravens corresponded to the expansion of habitat and climate. The species also adapted faster than any other prehistoric or modern bird included in the comparison.
“When we think about the processes of global diversification, it’s important to consider not just the ability to reach new places, but also the ability to survive once you’re there. Our work suggests that ravens and ravens diversified both rapidly and widely because they were particularly good at coping with different habitats,” said Carlos Botero, a biologist at Washington University in St. Louis and co-author of the study, in a press release. .
The authors note that the exact reasons for these processes are still not known. However, a high brain mass to body size ratio provides a greater ability to innovate and learn new behaviors, which could have helped crows and ravens survive longer in new environments. Combined with the physical abilities that allowed them to reach new habitats with a variety of niches, the study could hold the real answers behind corvid conquest.