(Roughly) Daily

“If locusts are ravenous sociopaths, cicadas are more like frat boys – clumsy, loud, and obsessed with sex”*…

… and they are, themselves, the object of other species’ obsessions…

This spring’s emergence of periodical cicadas in the eastern U.S. will make more than a buzz. Their bodies—which will number in the billions—will also create an unparalleled food fest for legions of small would-be predators, including many birds and mammals. But some animals may benefit more than others, and any boost predator populations get from the coming buffet of winged insects will likely be short-lived, researchers say.

Tiny chickadees and mice have been known to wrestle these chunky bugs for a quick snack. Raptors, fish, spiders, snakes and turtles will gulp them down when given the chance. Captive zoo animals, such as meerkats, monitor lizards and sloth bears, will do so as well if the insects show up in their enclosure. Observers have even reported seeing domestic cats trap two cicadas at once, one under each forepaw.

This spring, three species of cicadas (collectively referred to as Brood X or Brood 10) will crawl out of the ground where they have spent the previous 17 years. They will coat the limbs and leaves of trees, sing, mate, lay eggs and then die. Uneaten corpses and body parts will add nutrients to the soil, bolstering the ecosystem and its denizens long after the boisterous insects disappear. But the famous periodicity of cicada broods can set some predators up for feast-then-famine scenarios—population booms followed by food insecurity and then sudden drops in numbers.

“In response to this superabundance of food, a lot of the predator populations have outrageously good years,” says Richard Karban, a University of California, Davis, entomologist who studies periodical cicadas. “But then the next year, and in the intervening years, there’s no food for them, so their populations crash again.”

Predators could be part of the reason that these slow-flying, defenseless and colorful cicadas emerge periodically instead of perennially. Over millennia, synchronized periodic emergences as a dense mob could have led to higher adult survival rates. Thus, the insects evolved to adopt their unusual life cycle—most of which is spent feeding underground—explains University of Connecticut evolutionary biologist and ecologist Chris Simon, who studies cicadas. “The predators are really important in driving the whole story,” she says. The success of the species effectively banks on sheer volume…

Most bird species do not travel to take advantage of cicada emergences… They live and eat in the same areas year after year, picking off the insects opportunistically instead of traveling to the cicada motherlode… cuckoos are an exception: they migrate to take advantage of insect outbreaks all over the country…

Despite all the eager predators, the life-cycle gamble on high-volume emergences pays off for periodical cicadas. Most survive predation to mate and then drop dead to the forest floor. But even if they go uneaten, their ecosystem impact does not stop there. Cicada bodies contain about 10 percent nitrogen, which is more than the concentration found in dead leaves and other typical forest litter, says Louie Yang, a University of California, Davis, entomologist, who studies resource pulses and phenological shifts. Plants such as American bellflowers will take up the nitrogen from the dead cicadas, and herbivorous mammals and insects will selectively feed on the higher-nitrogen fertilized leaves, he adds.

Patterns such as this one illustrate the ecological lens that periodical cicadas can provide on biological communities and evolutionary timelines. “I love the reciprocity of the whole system,” Yang says. “I think this kind of stuff happens all the time, but it’s usually hard to see. When these pulse events happen, it makes it really obvious—we can see that pulse pass through the system.”…

Billions of emerging insects will likely trigger predator population surges: “Brood X Cicadas Could Cause a Bird Baby Boom.”

Oh, and given climate change, 17-year cicadas could become 13-year cicadas: “The cicadas are coming. And they’re changing dramatically.”

* Catherine Price, 101 Places Not to See Before You Die


As we bear the buzz, we might recall that it was on this date in 1923 that insulin became publicly available for use by diabetics. Frederick Banting had discovered insulin in 1921, and refused to put his name on the patent. He felt it was unethical for a doctor to profit from a discovery that would save lives. He and his co-inventors, James Collip and Charles Best, sold the insulin patent to the University of Toronto for a mere $1. They wanted everyone who needed their medication to be able to afford it.

Today, Banting and his colleagues would be spinning in their graves: Their drug, which many of the 30 million Americans with diabetes rely on, has become the poster child for pharmaceutical price gouging.

The cost of the four most popular types of insulin has tripled over the past decade, and the out-of-pocket prescription costs patients now face have doubled. By 2016, the average price per month rose to $450 — and costs continue to rise, so much so that as many as one in four people with diabetes are now skimping on or skipping lifesaving doses


Written by LW

April 15, 2021 at 1:01 am

%d bloggers like this: