Wolf genes make the coyotes of northeastern North America bigger and stronger than those elsewhere.
Image: KITCHIN AND HURST/ALL CANADA PHOTOS/CORBIS
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By Sharon Levy of Nature magazine
Near the dawn of time, the story goes, Coyote saved the creatures of Earth. According to the mythology of Idaho's Nez Perce people, the monster Kamiah had stalked into the region and was gobbling up the animals one by one. The crafty Coyote evaded Kamiah but didn't want to lose his friends, so he let himself be swallowed. From inside the beast, Coyote severed Kamiah's heart and freed his fellow animals. Then he chopped up Kamiah and threw the pieces to the winds, where they gave birth to the peoples of the planet.
European colonists took a very different view of the coyote (Canis latrans) and other predators native to North America. The settlers hunted wolves to extinction across most of the southerly 48 states. They devastated cougar and bobcat populations and attacked coyotes. But unlike the other predators, coyotes have thrived in the past 150 years. Once restricted to the western plains, they now occupy most of the continent and have invaded farms and cities, where they have expanded their diet to include squirrels, household pets and discarded fast food.
Researchers have long known the coyote as a master of adaptation, but studies over the past few years are now revealing how these unimposing relatives of wolves and dogs have managed to succeed where many other creatures have suffered. Coyotes have flourished in part by exploiting the changes that people have made to the environment, and their opportunism goes back thousands of years. In the past two centuries, coyotes have taken over part of the wolf's former ecological niche by preying on deer and even on an endangered group of caribou. Genetic studies reveal that the coyotes of northeastern America — which are bigger than their cousins elsewhere — carry wolf genes that their ancestors picked up through interbreeding. This lupine inheritance has given northeastern coyotes the ability to bring down adult deer — a feat seldom attempted by the smaller coyotes of the west.
The lessons learned from coyotes can help researchers to understand how other mid-sized predators respond when larger carnivores are wiped out. In sub-Saharan Africa, for example, intense hunting of lions and leopards has led to a population explosion of olive baboons, which are now preying on smaller primates and antelope, causing a steep decline in their numbers.
Yet even among such opportunists, coyotes stand out as the champions of change. “We need to stop looking at these animals as static entities,” says mammalogist Roland Kays of the North Carolina Museum of Natural Sciences in Raleigh. “They're evolving”.
At a fast rate, too. Two centuries ago, coyotes led a very different life, hunting rabbits, mice and insects in the grasslands of the Great Plains. Weighing only 10 to 12 kilograms on average, they could not compete in the forests with the much larger grey wolves (Canis lupus), which are quick to dispatch coyotes that try to scavenge their kills.
The big break for coyotes came when settlers pushed west, wiping out the resident wolves. Coyotes could thrive because they breed more quickly than wolves and have a more varied diet. Since then, their menu has grown and so has their range; they have invaded all the mainland United States (with the exception of northern Alaska) and Mexico, as well as large parts of southern Canada.
The animals that arrived in the northeastern United States and Canada in the 1940s and 50s were significantly larger on average than those on the Great Plains, sometimes topping 16 kilograms. Kays and his colleagues studied the rapid changes in coyote physique by analyzing mitochondrial DNA and skull measurements of more than 100 individuals collected in New York state and throughout New England. They found that these northeastern coyotes carried genes from Great Lakes wolves, showing that the two species had interbred as the coyotes passed through that region. “Coyotes mated with wolves in the 1800s, when wolf populations were at low density because of human persecution,” says Kays. In those circumstances, wolves had a hard time finding wolf mates, so they settled for coyotes.
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8 Comments
Add CommentIt seems almost politically incorrect to read about a successful wild animal.
Reply | Report Abuse | Link to thisI believe there is a First Nations story that when the last man on Earth finally dies there will be a coyote, just out of reach, watching him and laughing.
Reply | Report Abuse | Link to thisI wait the news that NRA farmers have risen to thwart this nature-created solution to deer populations explosions (caused by NRA- & farmer-supported near-extinction of natural predators) by declaring evolving coyotes to be threats that they then hunt to near extinction.
Reply | Report Abuse | Link to thisThere have been bounties and traps for coyotes here in the Northwest for many years, Coyote hunting is a popular "sport" with very high powered, accurate, and "flat" trajectory rounds. Coyotes are fast, small, and smart. They are evidently evolving faster than the hunters as there are still a lot of them left. There used to be a market for coyote fur but with the anti-fur movements this has mostly dried up. These people were the most effective coyote preditors
Reply | Report Abuse | Link to thisI hope the researchers are correct about the coyote controlling deer herds. I have my doubts. Having managed a 300 acre farm in south central WIsconsin for nearly 50 years, I do not believe the arrival of coyotes had any effect on the deer population at all. Our property has been perpetually at 50-100 deer per square mile even though coyotes showed up in force 20 years ago.
Reply | Report Abuse | Link to thisThe only force that has had any effect has been has been human predation. Over the past 5 years using state sanctioned hunting, we have been able to reduce the herd to 10-15 deer. This is still to many but with the reduction in browsing, the native plant species have rebounded to an amazing degree.
Hopefully the coyotes and wolves can keep these numbers at the current levels but as far as bringing down excessive population densities, I have my doubts.
SSM why not try farming deer as we do here in New Zealand. The venison market can be very lucritave.
Reply | Report Abuse | Link to thisUrban animals are probably all starting to diverge from their rural counterparts. In urban areas, their main "predator" is a vehicle and it doesn't behave properly. Urban animals should be starting to display adaptive responses. In some animals this might be showing up as truncation, and replacement of one set of behaviours for another. In others their should be the beginnings of increases in neural networks to hold their old survival and new survival behaviours.
Reply | Report Abuse | Link to thisThere were coyotes in Arlington in the early 90's. If they weren't seen in Rock Creek Park until 2004, it's because nobody was paying attention. I used to see them in our neighborhood off Military Rd, and there was a female with pups around Marymount I observed over several years.
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