My AP Biology Thoughts  Unit 7 Natural Selection EPISODE TITLE: The Evolution of CoywolvesKeenan: Welcome to My AP Biology Thoughts podcast, my name is Keenan Wallace and I am your host for this podcast. In episode 115, we will be discussing the topic of Coywolves and how they relate to the AP Biology Curriculum.  Keenan: For this episode, we’ve brought in Alex Profit and Serena Russel to discuss the evolution of coywolves. So, to start us off: what exactly is a Coywolf? Alex: Well, ‘Coywolf’ is actually just a nickname for what is known to the scientific community as an eastern coyote. Eastern coyotes are hybrids of coyotes, wolves and dogs, however they are still primarily coyotes and remain as coyotes rather than wolves.  Keenan: So you say that the Coywolves, or eastern coyotes are a mix of several different species. Do you know the genetic breakdown? Serena: It’s difficult to say for certain since the coyotes’ genetic makeup varies by region and population, but according to a DNA analysis done by Evolutionary Biologist Javier Monzón, they are 64% coyote, 13% gray wolf, 13% eastern wolf, and 10% dog.  Keenan: Wow, that’s some genetic diversity. So how do these new hybrids differ from their pure coyote ancestors? Alex: For one thing, they’re larger. Eastern Coyotes are 35-37% larger than their western counterparts. They also have larger and more powerful heads, their ears are more rounded like a wolf’s and they have wolf-like fur markings. There’s lots of variation within and between populations, but coywolves' features tend to match the midpoint between coyotes and wolves.  Keenan: Fascinating! So from what I understand, this interbreeding is a fairly recent development. What led to it? Serena: This story started several hundred years ago with the arrival of Europeans in the Americas. When Europeans colonized the East Coast of America they started cutting down forests and hunting large prey in the region, which threatened the habitat and food source of local grey wolves. At the same time, western coyotes, which are adapted to more open terrain, were drawn east by the expansion of their preferred habitat via deforestation. With shrinking numbers of grey wolves and a new thriving population of coyotes in the region, it makes sense that the wolves soon turned to coyotes as mating partners.  Serena: From there, natural selection took over. With the right mix of coyote and wolf DNA, a new species was created that was the best of both worlds. These “coywolves,” as they are called, are larger than coyotes, but inherited the social nature of wolves, meaning they form packs to hunt, which allows them to hunt large animals like deer in addition to the small prey that coyotes usually feed on. On top of that, they possess the strong ability of coyotes to adapt to urban environments, and are comfortable in both open and forested environments.  Keenan: I can see why this mixing would be beneficial, but is it considered evolution, or just hybridization?  Serena: Both....