Coyotes as Proxy for Urban Evolution

Urbanization has been ever increasing since the start of the industrial revolution and has shown no signs of slowing down. This has lead to cities growing bigger and bigger and thereby imposing new selection pressures on the animals in them. However, quantifying the effects of anthropogenic selection pressures has proven difficult for non-model species due to a variety of reasons (Kreling et al, 2024).

The gold standard in evolutionary research remains genomic analysis. Genomic analysis however, remains an expensive and time consuming method, especially when the genome is still undiscovered. When genomic differences are known an often used way to differentiate between beneficial and non-beneficial mutations is by using a common garden experiment. In a common garden experiment organisms from different populations are grown together under the same controlled conditions to study the effect of genetic differences.  However not all organisms are suitable for such experiments. Recently researchers have suggested looking to coyotes (Canis latrans) as a way to circumvent these problems (Kreling et al, 2024).

Coyotes are originally a rural carnivore hunting on diverse prey ranging from deers to birds to fish, the coyote has been greatly increasing in number in urban areas. Their tolerance to a highly diverse diet, combined with high levels of intelligence and their semi-nocturnal lifestyle has made them great at adapting to life in the city (Gelmi-Candusso et al., 2024). They also share a close evolutionary history with both wolves and domestic dogs.  As the genome of domestic dogs is very well studied researchers argue that it can be used as a proxy for the coyote genome. By knowing which genes to look for, as well as their supposed function research can be done in a much more timely fashion, as well as being much cheaper.

By looking at domestic dog DNA researchers have proposed an extensive list of genes to research in coyotes. They have selected these genes by hypothesizing which traits are most likely to be influenced by anthropogenic factors. The traits that are being focused on are diet, immunology and thermoregulation, behaviour, cognition and neuroanatomy and finally reproduction and sexual selection (Kreling et al., 2024) .

Food found in urban areas have a very different nutritional profile than food found in non-urban areas. Urban food has a higher caloric density due to high levels of carbohydrates and fat, but a lower nutritional value because of lower levels in proteins. This change in nutritional intake has been linked to different levels of insulin production and diabetes. Furthermore researchers further hypothesize that due to a decrease in hunting activity due to readily available food in the anthropogenic environment both skull size and teeth size might decrease (Larson et al., 2020).

Researchers expect differences between rural and urban populations researchers expect to also find differences in ummunology and thermoregulation. When living in urban areas coyotes also come into contact with much higher levels of pollutants and antimicrobial properties in their diet. Which could lead to selection for genes that help deal with these stressors. As urban areas are well-known for being heat islands increased levels of thermoregulation are also expected to be found (Kreling et al., 2024).

Urban areas also provide coyotes with a different set of problems to solve. This causes a very broad range of different selection pressures, from avoiding humans to accessing readily available food. Urban areas require wildlife to make more decisions and asses more new and changing situations than rural areas do. Researchers therefore expect an increase in cognition. Finally reproduction can be heavily altered by urban environments. Due to the close proximity of food it is expected that territories decrease in size as roaming is more of an energy investment with little payoff. Combined with the surplus of available food usually results in larger litters and an increase in offspring frequency (Kreling et al., 2024).

It is well established that urban areas create a novel ecosystem for wildlife, and coyotes have been found to thrive in it due to a variety of reasons mentioned above. As a non-model species it  is usually expensive and time consuming to do evolutionary research into these non-model species. However due to their close ancestry to domestic dogs, coyotes provide an unique opportunity to study anthropogenic evolution. Candidate genes are much easier identified and understood due to this close ancestry. Therefore research into coyotes can help us identify the directions of anthropogenic evolution in a large mammalian carnivore.

 

References:

Gelmi-Candusso, T. A., Wheeldon, T. J., Patterson, B. R., & Fortin, M. J. (2024). The effect of urbanization and behavioral factors on coyote net displacement and its implications for seed dispersal. Urban Ecosystems, 27(2), 387-397.

Kreling, S. E., Vance, S. E., & Carlen, E. J. (2025). Adaptation in the Alleyways: Candidate genes under potential selection in urban coyotes. Genome Biology and Evolution, 17(1), evae279.

Larson, R. N., Brown, J. L., Karels, T., & Riley, S. P. (2020). Effects of urbanization on resource use and individual specialization in coyotes (Canis latrans) in southern California. PLoS One, 15(2), e0228881.

 

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