Small marsupials in Australia may struggle to adjust to a warming climate

FEBRUARY 12, 2020

by Frontiers

Numerous questions remain unanswered as to how the planet's species will respond to climate change. A new paper in the journal Frontiers in Physiology suggests that at least one species of marsupial "mice" may struggle to adapt to a warming world.

The study found that changes in ambient temperatures experienced during the development and growth of yellow-footed antechinus (Antechinus flavipes) can influence their behavioral and physiological traits.

"This has important implications in terms of how this species will respond to changes in the climate," said lead author Dr. Clare Stawski, associate professor at Norwegian University of Science and Technology. "Individuals raised in warm conditions appear to have less phenotypic flexibility, suggesting that they may not be able to respond effectively to prolonged increases in temperature."

Phenotypic flexibility refers to the ability of an organism to adjust to a new type of environmental stress. In this case, Stawski and colleague Dr. Fritz Geiser, a professor at the University of New England in Australia, wanted to see how antechinus might respond to temperature swings for varying time periods.

The experiment involved 19 juvenile antechinus, which were split into two groups and subjected to different temperature regimes ranging from 16.7 degrees Celsius to 24.7 degrees Celsius. Infrared sensors attached to individual cage lids measured their activity and custom-made data loggers recorded their behavior.

Once the miniature marsupials reached adult age, the scientists measured metabolic rates, body mass and other physiological parameters across another set of experiments. These included putting them into temperature-controlled chambers where they experienced further variations in temperatures.

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Warming climate could see butterfly loved by Churchill return to UK

Former PM unsuccessfully tried to reintroduce black-veined white in 1940s, but conditions may now allow species to prosper

Patrick Barkham

Sat 7 Apr 2018 06.30 BST

He was the consummate politician who could bend nations to his will, but Winston Churchill was powerless when it came to butterflies.

The British prime minister hired the country’s leading lepidopterist and spent years attempting to reintroduce two extinct species into his back garden.

Despite his best efforts, and the release of hundreds of black-veined whites and swallowtails in the 1940s, his schemes to have rare butterflies feasting on “fountains of honey and water” at Chartwell in Kent were an ignominious failure.

Churchill may, however, simply have been seven decades ahead of his time: new research has revealed that climatic conditions may be suitable for the black-veined white to fly in Britain once again.

The species – which is still found across much of Europe – became extinct in Britain after a series of disastrously wet autumns in the early part of the 20th century. Now, with average temperatures rising, experts believe it could prosper here once again.

Two studies in northern France, which has a similar climate to southern England, have found that it would be easy to provide for the black-veined white’s needs by creating flowery field margins and allowing the growth of young scrub such as hawthorn and blackthorn.

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Climate change, beetle may doom rugged pine

SAWTOOTH RIDGE, Okanogan County — The bug lady scoots through stick-straight lodgepole and ponderosa, and marches uphill toward the gnarled trunk of a troubled species: the whitebark pine.

The ghostly conifers found on chilly, wind-swept peaks like this may well be among the earliest victims of a warming climate. Even in the Northwest, rising temperatures at higher elevations have brought hundreds of thousands of whitebark pines in contact with a deadly predator — the mountain pine beetle — that is helping drive this odd tree toward extinction.

Connie Mehmel, with the Okanogan-Wenatchee National Forest, is one of a handful of entomologists struggling to track the beetles' destructive path.

Mountain pine beetles are probably best-known here as the trunk-girdling devils that have reddened and deadened millions of acres of lodgepole, exposing the Northwest to a greater potential for cataclysmic wildfires. But the evolutionary history of lodgepole pine and beetles is so intertwined that those forests in many places are expected to grow back.

Whitebark pines may not.

"What concerns me and a lot of people in my line of work is we are seeing beetles being more active in areas where we didn't use to see them — particularly in higher-elevation areas," Mehmel says. "We have thousands of acres of whitebark pine that are being attacked by mountain pine beetles, more than we've seen in quite a long time."
Much attention has been paid to the way pine beetles have gnawed through whitebark forests in the Northern Rockies, particularly in Yellowstone National Park, where the trees' seed cones provide important food for grizzly bears.

But the beetles also are whittling away at whitebark in Northwest areas once thought safe from bugs.

When it comes to the number of acres or trees killed by beetles and an invasive fungus called white pine blister rust, hard data typically requires aerial surveys and is frustratingly inexact. Researchers instead focus on trend lines.

And in the Northwest, they all point in one direction. A study in the mid-2000s showed whitebark trees had declined by 41 percent in the Western Cascades. Tree declines throughout Washington and Oregon hovered around 35 percent. In the coastal range and the Olympics, blister rust infection ranged from 4 to 49 percent. Nearly 80 percent of the whitebark in Mount Rainier National Park are infected. Whitebark deaths in North Cascades National Park doubled in the last five years.


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'Heat-Proof' Eggs Help Turtles Cope With Hot Beaches

ScienceDaily (Sep. 26, 2011) — Sea turtles face an uncertain future as a warming climate threatens to reduce their reproductive viability. However, new research led by the University of Exeter and published this week in Proceedings of the Royal Society B shows that some turtles are naturally heat-tolerant.

The study focused on green turtles nesting on Ascension Island, a UK overseas territory in the South Atlantic Ocean. Scientists from the Universities of Exeter and Groningen found that eggs laid by turtles nesting on a naturally hot beach withstand high temperatures better than eggs from turtles nesting on a cooler beach just a few kilometres away.

The warmer beach has dark sand, whereas the neighbouring beach is two to three degrees Celsius cooler because it has white sand. Green turtles travel from the coast of South America to the tiny island to nest. Most female turtles nest on the beaches where they themselves hatched, so populations can become adapted to specific nesting locations.

The researchers placed some of the eggs laid on each beach into incubators of either 32.5 degrees Celsius or 29 degrees Celsius and monitored their progress. They found that the eggs from the warmer beach were better able to thrive in the hot incubator than those from the cooler beach.

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