QUICK FACTS
Identify: Virginia opossum (Didelphis virginiana)
The place it lives: Central and North America
What it eats: Fruit, bugs, small animals and carrion
With their beady eyes, massive ears, hairless tails and quick, stocky legs, opossums are distinctive marsupials. Regardless of their odd look, these animals have a wealthy evolutionary historical past and have remained largely unchanged for thousands and thousands of years. Their exceptional skill to adapt to completely different environments, meals sources and predators has helped them survive from the time of the dinosaurs to immediately.
The Virginia opossum is the one opossum species present in the US and Canada. Opossums have the smallest brain-to-weight ratio of any North American mammal.
The earliest identified family members of recent opossums lived over 65 million years in the past, across the time dinosaurs went extinct. A 2009 research revealed in PLOS ONE discovered that peradectids, a household of marsupials identified from fossils largely in North America and Eurasia, are the closest extinct family members of residing opossums. Like fashionable opossums, peradectids had opposable thumbs on their hind toes and a equally formed cranium — options which have remained almost unchanged for thousands and thousands of years. The earliest opossum fossils date again to the early Miocene epoch, roughly 20 million years in the past.
One key cause why opossums have survived for thus lengthy with few modifications is as a result of they’re adaptable. These marsupials eat virtually something, together with fruit, bugs, small animals and animal carcasses. They will reside anyplace from forests to city backyards. And, though they’re largely nocturnal, they will generally be seen in daylight if meals is scarce.
Opossums are additionally proof against snake venom, significantly that of rattlesnakes and different pit vipers. This resistance is because of a protein referred to as Deadly Toxin Neutralising Issue discovered of their blood, which might neutralize varied toxins in snake venom. This permits opossums to prey on venomous snakes that may in any other case be a risk.
Opossums give start to underdeveloped younger, which crawl right into a pouch and nurse for round eight weeks as they develop. Younger opossums then experience on their mom’s again for a number of weeks till they grow to be unbiased at 12 weeks previous.
When threatened, opossums could growl, hiss, naked their enamel or climb a close-by tree to flee. If escape is not doable, they resort to “taking part in useless” — a protection mechanism generally known as thanatosis.
This response is not a acutely aware resolution however a physiological response to excessive stress. It causes the opossum to grow to be fully motionless and seem lifeless. This habits is commonly accompanied by a vital drop in coronary heart and respiratory charges, a lower in physique temperature and the discharge of a foul-smelling fluid from the anal glands. Collectively, these cues sign to predators that the opossum is already useless, typically inflicting them to lose curiosity and transfer on. So involuntarily “taking part in possum” permits the animals to outlive the encounter.