[ad_1]
Black fur, white stripes, fanny full of smelly liquid – anyone can identify the striped skunk. But did you know that these smelly mammals have a number of smaller cousins marked with a black and white Rorschach spot pattern? They’re called spotted skunks and they do something that stripeys can’t.
Spotted skunks perform an extended pear tree before spraying you.
“I jokingly call them the acrobats of the skunk world,” said Adam Ferguson, a little carnivorous biologist at the Field Museum in Chicago.
Now that you’ve encountered the spotted skunk, here’s another important fact: there is more than one species, and analyzing the difference between them is tricky. For starters, smelly butts all look the same. Nowadays, most scientists agree that there are four species of spotted skunks, although previous research indicated that there were only two or fourteen.
Still, the researchers have a new answer to this question which they published Thursday in the journal Molecular Phylogenetics and Evolution. It is based on more than 200 DNA samples taken from spotted skunks, some of which were killed on the road, in places ranging from British Columbia to Costa Rica.
“There are certainly seven species,” says Molly McDonough, phylogenomics at Chicago State University and research associate at the Field Museum and the Smithsonian’s Museum of Natural History.
Dr McDonough and Dr Ferguson, the co-authors of the new study, are also married. She calls him the Skunk Wrestler, and he calls her the Lab Sorcerer. When he proposed, he even slipped the ring into a box of DNA prep products.
It’s like they say, the couple who get sprayed together, stay together.
“If you approach the skunk very gently and gently, it tends not to vaporize,” Dr. Ferguson said. “But I say skunks are like people. Some of them are just fools.
Even though spotted skunks do everything they can to keep researchers at bay, there are several compelling reasons to study pint-sized carnivores.
For example, now that researchers have mapped seven distinct lineages based on genomic similarities, they can see that spotted skunks have diversified much more than their close relatives, striped skunks, and pig-nosed skunks (which look a bit like to a skunk version of a black and white cookie). It’s curious, and scientists suspect it has something to do with spotted skunks being the smallest stinker in North America.
“We’re sort of speculating that they are more rodent-like,” Dr Ferguson said, referring to the inability of two-pound skunks to travel very far in any direction and their cycles. relatively rapid reproduction.
These factors appear to have allowed spotted skunks to branch out into new species during the last ice age and its changes in the North American climate.
The researchers also found that most species of spotted skunks could be divided into two groups, or clades, of which three were native to the east and three to the west. (The seventh species of spotted skunk, Spilogale yucatanensis, is a bit bizarre, being native to the Yucatán Peninsula in Mexico but sharing the closest evolutionary relationship to S. putorius, native to Florida and the Southeastern United States.)
The biggest distinction between the two clades is that they appear to reproduce in entirely different ways. In the eastern clade, females tend to be pregnant for around 50 to 65 days, mating in March or April and giving birth in May or June. In the west, spotted skunks typically breed in the fall around September or October, then give birth in April or May for a total gestation period of 180-200 days.
How is it possible? There is some evidence that Western skunks use a strategy known as delayed implantation, where a fertilized egg enters a period of dormancy before it develops. Females of many species of mammals, from bats to bears, use this practice to conserve resources and survive seasonal food shortages.
And because representatives of both clades have overlapping territories in places like Texas, you might have two spotted skunks in the same location that look identical but apparently cannot reproduce because their breeding strategies are incompatible.
So what’s it like to study skunks with your partner? Well, once upon a time in Mexico, a pig-nosed skunk had just sprayed Dr. Ferguson in the face, rendering him temporarily blind.
“As I was running screaming for water, she actually asked me, ‘Am I helping you or am I catching the skunk?’ “, he said.
Not wanting to lose the data point, Dr. McDonough grabbed the skunk.
[ad_2]
Source link