Research suggests that sharp rise in water temperatures led to death and disappearance of some species from the shallow water of Israeli shores — ScienceDaily

Researchers from Tel Aviv University (TAU) embarked on an underwater journey to solve a mystery: Why did sponges of the Agelas oroides species, which used to be common in the shallow waters along the Mediterranean coast of Israel, disappear? Today, the species can be found in Israel mainly in deep habitats that exist at a depth of 100 meters (330 feet).

The researchers believe that the main reason for the disappearance of the sponges was the rise in seawater temperatures during the summer months, which in the past 60 years have risen by about 3°C (37°F).

The study was led by Professor Micha Ilan and PhD student Tal Idan of TAU’s School of Zoology at the George S. Wise Faculty of Life Sciences and Steinhardt Museum of Natural History. The article was published in the journal Frontiers in Marine Science in November 2020.

“Sponges are marine animals of great importance

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Some tropical forests show surprising resilience as temperatures rise

The world’s hottest rainforest is located not in the Amazon or anywhere else you might expect, but inside Biosphere 2, the experimental scientific research facility in the desert outside Tucson, Arizona. A recent study of tropical trees planted there in the early 1990s reported a surprising result: They have withstood temperatures higher than any likely to be experienced by tropical forests this century.

The study adds to a growing tally of findings that are giving forest scientists something that’s been in short supply lately: hope. Plants may have unexpected resources that could help them survive—and perhaps even thrive—in a hotter, more carbon-rich future. And while tropical forests still face both human and natural threats, some researchers believe dire reports of their impending decline due to climate change may have been exaggerated.

“Biology is ingenious,” says Scott Saleska, an ecologist at the University of Arizona in Tucson and co-leader of the

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Late-season Arctic research cruise reveals warm ocean temperatures, active ecosystem — ScienceDaily

Arctic researchers Jacqueline Grebmeier and Lee Cooper have been visiting the Bering and Chukchi seas off Alaska for nearly 30 years, collecting information about the biological diversity of the watery world under the sea ice to understand how marine ecosystems are responding to environmental changes. This year, a late-season research cruise in October revealed a surprise. At a time of year when an ice-breaking ship is usually required to get them to some of the data-gathering outposts, scientists found nothing but open water and an unusually active ecosystem.

“The water and air temperatures were warmer, and we had ecosystem activity that normally doesn’t occur late in the season,” said University of Maryland Center for Environmental Science Research Professor Jacqueline Grebmeier, chief scientist on the research cruise and a national and international leader in Arctic research.

Grebmeier and Cooper were part of a small team of researchers from the University of

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Shifts in water temperatures affect eating habits of larval tuna at critical life stage — ScienceDaily

Small shifts in ocean temperature can have significant effects on the eating habits of blackfin tuna during the larval stage of development, when finding food and growing quickly are critical to long-term survival, a new study from Oregon State University researchers has found.

In a year of warmer water conditions, larval blackfin tuna ate less and grew more slowly, in part because fewer prey were available, compared to the previous year, when water conditions were one to two degrees Celsius cooler, the researchers found.

The findings provide new insight into the relationship between larval tuna growth and environmental conditions, as well as the broader impacts of climate change on marine fish populations. As the climate continues to warm, over the long term, increasing water temperatures may interact with changing food webs to pose critical problems for fish populations, the researchers said.

“There was a drastic difference in the fish between

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Project using roundworms uncovers a mechanism that leads to male infertility caused by high temperatures — ScienceDaily

University of Oregon biologists have used the model organism Caenorhabditis elegans to identify molecular mechanisms that produce DNA damage in sperm and contribute to male infertility following exposure to heat.

In humans, the optimal temperature for sperm production is just below body temperature, in a range of about 90-95 degrees F. Human studies have found that exposure to temperatures as little as 1 degree C (1.8 F) above this normal range adversely affects male fertility, said Diana Libuda, a professor in the Department of Biology and Institute of Molecular Biology.

The phenomenon of heat-induced male infertility is well known, and the effects of modern exposures to heat such as hot tubs, tight clothing and excessive drive times have been extensively studied. The underlying mechanisms that damage sperm and impair fertilization are not completely understood.

“In both humans and C. elegans, relatively small increases in temperature are sufficient to reduce male

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The effects of wildfires and spruce beetle outbreaks on forest temperatures — ScienceDaily

Results from a study published in the Journal of Biogeography indicate that wildfires may play a role in accelerating climate-driven species changes in mountain forests by compounding regional warming trends.

The study examined temperatures within forests in a region of Colorado that has experienced wildfires and spruce beetle outbreaks within the last 10 to 15 years. Researchers used a network of sensors to record temperatures for a full year in burned and beetle-impacted areas.

Burned areas were warmer than unburned forest. Conversely, canopy loss (the upper layer of trees) in unburned, beetle-killed forests resulted in slight cooling. This difference may be attributed to differing effects of each disturbance type on understory cover and residual canopy.

“We tend to assume that disturbances are going to catalyze climate change-driven forest declines, but we found that the type and severity of the disturbance matters,” said lead author Amanda Carlson, PhD, of Colorado State

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