evolutionary biology

An analysis carried out in the United States has shown that, through intensive breeding and artificial selection, humans have pushed breeds such as pugs and Persian cats to evolve with very similar skulls and flattened faces. These two species, which have a common ancestor but have been evolutionarily separated for 50 million years, have converged to the point where they resemble each other more than they do members of their own species or their ancestors. According to the study, published in PNAS, ‘this phenomenon has not been observed before in domesticated species.’ The authors lament that humans ‘have bred brachycephalic breeds to such an extreme that they are prone to respiratory, feeding and birthing problems and would not survive in the wild.’

The frequency of aggressive coalitions among female bonobos is associated with greater power over males, according to a study published in Communications Biology. The analysis is based on observations of six wild bonobo communities in the Democratic Republic of Congo between 1993 and 2021.

The company Colossal Biosciences has announced the birth of what they call three ‘dires wolves’, Romulus, Remus and Khaleesi, as reported in Time. The puppies, conceived in domestic dogs, were born thanks to genetic engineering techniques and ancient DNA to resemble a species that became extinct over 10,000 years ago.

One characteristic that is considered distinctive of human language is its capacity to combine elements and form more complex and meaningful structures, which is known as compositionality. Its most complex form, in which meaning is not simply the result of the sum of words, has not been found in any other animal species. Now, an international team claims to have observed it for the first time in bonobos. The results, published in Science, call into question assumptions about the uniqueness of human language and open up new avenues for understanding the evolution of communication, according to the journal.

Colossal Biosciences has announced the creation of genetically modified mice with characteristics reminiscent of the fur of extinct mammoths, such as fur colour, texture and thickness. The non-peer-reviewed results were shared today in the BioRXiv prepublication repository.

Peto´s paradox is the lack of observed relationship between the size of an animal and the prevalence of cancer, despite the fact that the greater number of cells and divisions as they get larger should increase the likelihood of cancer. A new study disproves this paradox by finding that, at least in terrestrial vertebrates, larger species do develop more cases of cancer. In quite a few of them, however, the increase is less than would be expected, suggesting that they have evolved anticancer mechanisms that remain worth studying. The results are published in the journal PNAS.  

Some animal species, such as parrots or dolphins, appear to address each other by imitating sounds from the receiver. However, animals addressing each other by individual names has only been observed in humans. Now, an international team of researchers says that African elephants can communicate through name-like calls and do not appear to rely on imitation to do so. According to the authors, who publish their results in the journal Nature Ecology & Evolution, the finding would imply that they have some degree of symbolic thinking. 

Chimpanzees can learn a new skill by observing each other — a phenomenon known as social learning — according to a study published in Nature Human Behaviour. The findings suggest that chimpanzees may have the capacity for cumulative cultural evolution, which was previously considered to be an exclusively human trait.