The continents, the solid blocks of land beneath our feet, weren’t always as strong as they’ve come to be. Now, scientists from Monash University in Australia have devised a new mechanism to explain how the roots of the continents—cratons—came to be. Using numerical models to simulate the conditions of Archean era Earth, the researchers’ findings, published in Nature, show that a strong base for the continents emerged from the melting and stretching of the cratonic lithospheric mantle.
Cratons form the base of continents and hold the title of the oldest existing portion of the lithosphere. They’re extremely thick and began to form up to 3 billion years ago, in the Archean eon. “They’re the secret keepers of the Earth,” said Catherine Cooper, an associate professor of geophysics in the School of the Environment at Washington State University in Pullman. Cooper was not involved in the new research. By studying cratons, scientists might learn how major components of Earth arose and how plate tectonics began. “If you can understand the role of the secret keepers within [Earth], then we can try to answer some of those questions better.”
As scientists gain a firmer grasp of the origins of cratons, they’re better able to understand processes that might be happening within other planets as well as the processes that helped form our own. “[Cratons] have kind of gone along for the ride, picking up all of Earth’s secrets for all this time,” said Cooper. “They’re such an intriguing scientific story.”
Another wild cat was an unusual meal choice for a jaguar, so scientists are looking for the reason.
A camera trap at a watering hole in Guatemala’s Maya Biosphere Reserve captured some extremely rare footage of an unusual jaguar meal: an ocelot. The footage showed the male jaguar letting a tapir pass by and waiting it out to instead nab the cat. Washington State University described the event as a possible “sign of climate-change-induced conflict” in a statement on Tuesday.
Ecologists from WSU and the Wildlife Conservation Society (WCS) studied the footage and published a paper on the predator interaction in the journal Biotropica in late December.
The timing of the watering hole incident was important. It happened in March 2019 during a serious drought. “Although these predator-on-predator interactions may be rare, there may be certain instances when they become more prevalent, and one of those could be over contested water resources,” said study co-author WSU assistant professor Daniel Thornton.
The recovery of beavers may have beneficial consequences for amphibians because beaver dams can create the unique habitats that amphibians need.
That finding was reported by four WSU Vancouver scientists in a paper published in the journal Freshwater Biology. The research took place in the Gifford Pinchot National Forest of the Cascade Range, where the researchers identified 49 study sites either with or without beaver dams. The researchers found the beaver-dammed sites were 2.7 times higher in amphibian species richness than the undammed sites.
“Beaver-dammed wetlands support more of the amphibian species that need a long time to develop in water as larvae before they are able to live on land as adults,” said Jonah Piovia-Scott, assistant professor in the School of Biological Sciences and one of the authors of the article.
In addition to Piovia-Scott, the authors of the study are Kevan Moffett, assistant professor in the School of the Environment; John Romansic, former postdoctoral scholar in the School of Biological Sciences; and Nicolette Nelson, former graduate student in the School of Biological Sciences.
About 20 years ago, ambitious restoration projects had brought coho salmon back to urban creeks in the Seattle area. But after it rained, the fish would display strange behaviors: listing to one side, rolling over, swimming in circles. Within hours they would die — before spawning, taking the next generation with them. In some streams, up to 90 percent of coho salmon were lost.
“To be running into these sick fish was fairly astonishing,” said Jenifer McIntyre, now a toxicologist and professor at Washington State University who is part of a team that, years later, has finally solved the mystery of the dying salmon around Puget Sound. “In those early years, we debated intensely, what could be the cause of this?”
Partnering with a local fish hatchery run by the Suquamish Tribe, they decided to put the theory to the test, exposing fish to a mixture they created of chemicals they knew to be in roadway runoff, like heavy metals and hydrocarbons from motor oil. But the salmon were unaffected, even at surprisingly high concentrations.
Washington State University scientists have developed a new way to classify the ocean’s diverse environments, shedding new light on how marine biomes are defined and changed by nature and humans.
Newly published in Global Ecology and Biogeography, research by
Alli Cramer, a 2020 doctoral graduate of WSU’s School of the Environment, now at the University of California Santa Cruz, and WSU SoE Professor Stephen Katz revealed a new approach which sorts biomes based on their life-supporting potential and stability of the sea floor.
“This means that energy flow and mobility are common organizing forces across a wide variety of marine ecosystems,” Cramer said. “Despite their differences, coral reefs and deep-sea deserts respond to the same processes.”
The new method could help scientists, fisheries managers, and conservationists reconsider the richness and diversity of ocean biomes as well as the value of high productivity regions being impacted by humans.