The driver of a car motoring down a country road well after nightfall sees a small, dark shadow for less than an instant, then feels a slight thump under the vehicle and moves on. A rumpled ball of fur and broken bones tumbles off the edge of the pavement as another death in nature takes place.
But whether the end of life is caused by the frequent fatal encounters with a vehicle or one of the myriad natural forces at work in the outdoors, what happens next is quite predictable.
While there are no embalmers, no funerals, and no burials in the animal world, there is a series of agents that serve the role as nature’s undertakers. When death occurs, they arrive at the carcass in a seemingly well-orchestrated order, each one playing an essential part in the decomposition process.
Since many of these “road kill” fatalities occur at night, those first on the scene are the nocturnal opportunists, such as foxes, coyotes, raccoons, or opossums. They will tear at any exposed flesh or use their teeth to create openings in the fresh carcass.
“Then as the sun rises and starts to heat things up, the carcass would often begin to emit an odor, and that odor will attract another group of organisms,” said Kent Bekker, director of conservation and research at the Toledo Zoo. “There certainly does appear to be some sort of order to the decomposition of lifeforms.”
Bekker said temperature and moisture level play a role in which of nature’s undertakers work a decomposing creature and with what degree of intensity they consume the carcass. On a warm or sunny day, the heat will carry the scent of death aloft where turkey vultures, one of the rare members of the bird kingdom with a sense of smell, pick up the invitation.
Carrion is tops on the vultures’ menu, and their physical and physiological adaptation allows them to eat rotting flesh and decaying matter with little consequence.
“They are able to eat some amazing things that you would think might kill most other species,” Mr. Bekker said.
That includes dining on carrion that could already be covered in flies and maggots, other members of nature’s burial by consumption army of volunteers. “That is another aspect of decomposition that will take place fairly early on, with the dead animal being colonized by flesh flies and their maggots,” he said.
These insects are larger than houseflies and are quickly attracted to rotting matter. The females deposit hatched maggots on carrion to feed. Flesh flies are often joined at a feeding site by blow flies, with the meat of dead animals also being essential for the survival of their larvae.
Beetles also play a part in the consumption and disposal of decaying flesh, as do worms, snails, slugs, millipedes, and bacteria.
Once the flesh is gone and legions of other parasites have worked on the cartilage and skin, just the hair and bones remain. It might take a considerable amount of time, but mice and voles will gnaw on the bones to get the calcium those hold, and eventually what little is left of the creature is absorbed into the soil.
First Published October 29, 2017, 6:06 a.m.