Evolution and One Lost Boy Produce New Species of Bird in Two Generations, and for the first time we absolutely watched it happen #science #biology #evolution #Galapagos

Visit Kate Rauner on WordPress for Science News

Scientists identified the island and species their bird came from – here’s one of his brethren

What’s a species? What separates one species from another? The word may be a handy abstraction but it’s also fuzzy. Our words aren’t as precise as we might hope.

Consider the evolution of a new species of bird, in two generations, from a single lost finch spotted by a graduate student.

The arrival 36 years ago of a strange bird to a remote island in the Galapagos archipelago… mated with a member of another species resident on the island, giving rise to a new species that today consists of roughly 30 individuals.

The newcomer was a male that sang a different song, and was much larger with a larger beak than three finch species living on the island. Because the island was small and intensely studied, researchers were able to collect blood samples of the new male and track his breeding.

A species is a population that interbreeds within its own group but not outside. That doesn’t mean individuals can’t or won’t breed outside their group – and produce offspring that can also breed. Some species are isolated because they because they never bump into each other.

“Reproductive isolation is considered a critical step in the development of a new species.” The new male’s offspring looked different and sang a different song than the fiches around them. Since they had each other, they weren’t as desperate (or lucky? insistent?) as their father, so they mated with each other. That’s why they’ve been awarded the title of species.

Such intense inbreeding can exaggerate genetic diseases and weaknesses, but that isn’t obvious yet for these finches. Who knows? Problems may arise. Perhaps we’ll watch the demise of this new species in coming years.

This new species may say more about people than birds. The Galapagos finches continue to be fascinating birds, utterly unconcerned about human-created concepts, taxonomy, or language.

More at phys.org/news and many other outlets.

Advertisements

That Which We Call a Wolf #nature #biology #words #wolves #language

Mexican gray wolf - a little guy as wolves go, perhaps because life in desert mountains is hard. Looks a lot like a coyote to me.

Mexican gray wolf – a little guy as wolves go, perhaps because life in desert mountains is hard. Looks more like a coyote than the big wolves of Yellowstone.

Can a word become more important than the thing it names? I’ve thought about this before. We humans stuff nature into neat little categories because it makes a complex world easier on our brains.

We divide living things into species.

But what is a species?

A species is often defined as a group of individuals that actually or potentially interbreed in nature. In this sense, a species is the biggest gene pool possible under natural conditions… That definition of a species might seem cut and dried, but it is not… many plants, and some animals, form hybrids in nature.” berkeley.edu

If you add deep time to your definition, you’ll find “species” come and go on Earth despite the fact that evolution is a continuum.

Like a lot of the labels humans create, a species is a handy way to mostly-categorize and sort-of talk about an important topic. The word is fuzzy, but that doesn’t usually matter.

Until it does.

In America, we have a law (much loved and hated) that requires we spend money and limit certain economic activities to save “threatened and endangered species.”

Most Americans live in urban/suburban areas and never see large predators, but want to protect them. Rural folk like myself actually live with them, lose cattle and pets to them, and sometimes fear for human lives. My urban/suburban friends may get a taste of living with predators because some wolves (and definitely coyotes) live in their parks and backyards.

Total disclosure – I own no cattle, lost two pets to bears, and am willing to protect predators but think the government often handles the projects badly.

That brings me to the American Wolf. If gray wolves, red wolves, eastern wolves, and Mexican grey wolves are four species, they must be protected in all their various ranges. Science tells us something about this question:

  • Eastern and red wolves are genetically coyote/wolf hybrids – Princeton-UCLA study published in Science Advances
  • Mexican grey wolves come from a tiny captive stock (true as far as I know) and have interbred with coyotes and domestic dogs (common assertion here in Mexican grey wolf country – I can’t say, but it seems plausible.)

Researchers analyzed the complete genomes of 12 pure gray wolves (from regions without any coyotes), three pure coyotes (from regions without any gray wolves), 6 eastern wolves, and 3 red wolves. The results showed that eastern wolves are about 75 percent gray wolf and 25 percent coyote, while red wolves are about 25 percent gray wolf and 75 percent coyote – with almost no unique genetic material of their own.”  csmonitor.com

(Too bad my local Mexican grey wolf was not included in the study.)

Pro-wolf and anti-wolf groups have entrenched mutual distrust in my area. Their conflict runs so deep that beating the other guy often seems more important than the wolves.

So choose your side and remember that, in government, a word means whatever the law or the courts say it means. Which will not be what science or common-usage says it means. Remember your opponents are probably nice people with reasonable goals – try to keep an open heart so you can keep an open mind.

Maybe haiku will help:

Coyotes mate wolves
But Danes and Chihuahuas can’t
So what’s a species?