Good-Bye, Everglades? How Tiny Beetles Are Destroying Florida’s Precious Wetlands

Florida’s flora and fauna can’t seem to get a break. They’re getting hit with another piece of bad news just weeks after a tract of endangered forestland was sold to a property developer. This time, instead of Walmart and 88 acres of rockland, a fungus transmitted by the invasive redbay ambrosia beetle is overrunning the Everglades. So far, experts haven’t come up with a way to contain it.

The insect from southeast Asia carries a fungus that causes laurel wilt, a disease deadly to trees. It has decimated swamp bay trees across 330,000 acres in the Everglades since the condition was first identified in 2011, and it shows no signs of stopping. According to The Associated Press, the redbay ambrosia beetle likely entered the United States through a shipment of wood packaging.

The blight threatens to lay waste to the billion-dollar projects aimed at restoring the region. From a bird’s eye view and even from the highway that cuts through the fragile wetlands, one can easily make out the dried-up gray and brown trees, reports the news agency.

The future looks even grimmer. Exotic plants that may overrun the Everglades as a result of the devastation of swamp bays can fuel fires. Also, they’re not a source of food for native wildlife. The plants’ roots can damage the homes of endangered species in the area. According to the National Research Council, about 16 percent of the Everglades’ greenery isn’t native.

“We already have these problems with invasives that are almost too daunting. When you add laurel wilt to the mix, it’s only going to get worse,” Everglades National Park chief of biology Tylan Dean told the AP.

The South Florida Water Management District, the agency managing the restoration of the Everglades, has promised to ramp up efforts to monitor and maintain the swamp bay trees.

“It’s amazing how much of an impact this one little tiny beetle that’s no bigger than Lincoln’s nose on a penny has done,” Jason Smith, a forest pathology expert at the University of Florida, told the AP. “And it continues to spread.”

This summer he plans to gather samples of the surviving trees, hoping to propagate fungus-resistant seedlings to keep their population alive.

Earth Is On The Cusp Of A Sixth Mass Extinction

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Approximately 65 million years ago, when the dinosaurs went extinct,  75% of the planet's many species went with them. It was the world's fifth, and most recent, mass extinction event. 

Now, according to a July 25 review in the journal Science, the Earth seems to be at the cusp of a sixth mass extinction. Only this time, an asteroid is not to blame. We are.

"Human impacts on animal biodiversity are an under-recognized form of global environmental change," the team of ecologists and biologists warn in Science. "Among terrestrial vertebrates, 322 species have become extinct since 1500, and populations of the remaining species show 25% average decline in abundance." 

A third of all vertebrates, the scientists write, "are threatened or endangered."

There are several long-time drivers of what researchers call "defaunation" — the decline of various animal species. The study points to " overexploitation,  habitat destruction, and impacts from invasive  species" as continuing threats, but notes that soon, human-caused climate change will be the number one driver of defaunation. Diseases that come from pathogens introduced by humans are another growing threat.

The good news? We're not yet totally doomed. 

As David Biello writes in Scientific American:

To avoid the sixth mass extinction we will probably have to employ more aggressive conservation, such as  moving species to help them cope with a changing climate . Think re-wilding: reintroducing species like wolves or beavers that were once present in a given ecosystem but have since disappeared. Aggressive conservation might also mean killing off newcomer species to preserve or make room for local flora and fauna.

As another study in Science notes, we've already made headway in saving some animals from what seemed like certain ruin.

But if humans as a species don't want to take our chances with a sixth mass extinction, we need to start taking drastic measures now. The momentum is already moving against us.

Giant Ancient Sea Scorpions Had Bad Eyesight

By By Tanya Lewis, Staff WriterJuly 8, 2014 10:44 PM

Sam Ciurca, who collected the sea scorpion specimens,
with a life size model of one called Acutiramus.

Gigantic sea scorpions that lurked in the ocean more than 400 million years ago weren't as scary as they sound, a new study suggests.

The massive creatures, known as pterygotids, were the largest arthropods that ever lived, growing to be up to 6.5 feet (2 meters) long, with claws measuring up to about 2 feet (0.6 m). But contrary to what scientists thought, these animals may not have been true top predators.

"These things were almost certainly still predators of some kind, but the imagined notion that they were swimming around terrorizing anything that looked edible is probably an exaggeration," said Derek Briggs, a paleontologist at Yale University in New Haven, Connecticut, and co-author of the new study, published today (July 8) in the journal Biology Letters.

Pterygotids were a type of eurypterid, an extinct type of sea scorpion related to arachnids. These ocean-dwelling creatures lived between about 436 million to 402 million years ago, in the Silurian and Devonian periods, Briggs said. Their closest living relatives are horseshoe crabs or modern sea scorpions, he said.

Previously, these spooky sea monsters were thought to be fearsome predators, devouring armored fishes and giant cephalopods (related to modern squids and nautiluses). Their compound eyes and large claws seemed to suggest as much.

But more recently, a study revealed that pterygotid claws wouldn't have been strong enough to break into armored fish or cephalopod shells.

A pterygotid fossil

In the recent study, Briggs and his team set out to examine the eyes of these ancient sea scorpions, to determine whether they had good enough vision to be great hunters.

Some of the lenses in the creatures' eyes were big enough for researchers to see them without any help from technology, but others had to be viewed under an electron microscope. The team estimated the angle between the lenses and the size of the lenses, comparing them with the eyes of a smaller eurypterid relative and of modern arthropods.

Briggs and his team concluded that the giant arthropods actually had poor eyesight. They probably lived near the bottom of the sea and likely hunted soft-bodied animals in dark waters or at night, Briggs said. But the fossil evidence limits these interpretations, so it's hard to know for sure how the animals behaved, he added.

After about 35 million years, pterygotids died out, and "it's a good thing they did," Brigg said. "They wouldn't be good company."