NatureWrap: New to the tree of life

Pictured above is Hippocampus nalu, Africa’s first and only-known pygmy seahorse and one of 213 newly described plant and animal species added to the tree of life this year by the Californian Academy of Sciences.

Its colleagues include 101 ants, 22 crickets, 15 fishes, 11 geckos, 11 sea slugs, 11 flowering plants, eight beetles, eight fossil echinoderms, seven spiders, five snakes, two skinks, two aphids, two eels, one moss, one frog, one fossil amphibian, one fossil scallop, one sea biscuit, one fossil crinoid (or sea lily) and one coral.

Some were right under our noses. The pipefish pictured below (Stigmatophora harastii) can be found off the coast of Australia’s Botany Bay, a popular scuba diving site near Sydney. It doesn’t live exactly where it would be expected to live, however, allowing it to avoid scientific scrutiny, as well as marine competition.

Others are long gone. The amber fossil at right allowed scientists to identify the amphibian Yaksha peretti and determine that it likely used its tongue as a slingshot to catch prey, much like modern-day chameleons. This, they say, extends the evolutionary origins of this adaptation to 100 million years ago.

More than two dozen Academy scientists and many more collaborators throughout the world described this year’s newcomers, despite the unique challenges of COVID-19.

“Unfortunately, the pandemic is a symptom of our broken relationship with nature,” says Chief of Science Shannon Bennett. “These newly described species represent one aspect of a growing collective effort to mend that relationship.

“By improving our understanding of Earth’s biodiversity and bringing us more in touch with the natural world, each new species serves as an important reminder–as does the pandemic–of our vital role in protecting our planet’s ecosystems.”

Ravens aping apes

Ravens may have evolved sophisticated cognitive skills in much the same way as the great apes, a new study suggests.

European researchers put eight hand-raised ravens through a series of tests at four, eight, 12 and 16 months of age then compared their performance with that of 106 chimpanzees and 32 orang-utans in a previous study.

The tests included spatial memory, object permanence (understanding that an object still exists when it is out of sight) understanding relative numbers and addition, and the ability to learn from a human experimenter. In all but the first of these, the ravens matched the apes.

Performance varied between individuals, but the ravens generally did best in tasks testing addition and understanding of relative numbers and worst in tasks testing spatial memory.

Cognitive performance was similar from four to 16 months of age, suggesting, the researchers say, that raven skills develop rapidly in response to living in a constantly changing environment where survival and reproduction rely on cooperation and alliances.

They do caution, however, that they might just have been working with a smart group.

The research was led by Simone Pika, from the University of Osnabrück, and Miriam Jennifer Sima, from Max Planck Institute for Ornithology, both in Germany. The findings are published in the journal Scientific Reports.

Sparrows take to the herbs

Ravens aren’t the only clever birds. A new study suggests that sparrows use medicinal herbs to defend against parasites and improve the condition of their offspring.

Researchers from Australia, China and France have discovered that russet sparrows in China incorporate aromatic wormwood leaves into their nests.

“The phytochemical compounds within wormwood leaves reduced infestation of the nest parasites otherwise found there, which results in the production of healthier chicks,” says William Feeney from Griffith University, corresponding author of a paper in Current Biology.

The use of medicines is a complex behaviour. While several birds have been suspected of using herbal medicines in a manner similar to humans, it has proven difficult to verify.

“Using a series of behavioural experiments, we show that the birds actively seek out nest locations close to the available wormwood and resupply established nests with fresh wormwood leaves using gathered based solely on the leaves smell,” Feeney says.

“The nests containing wormwood leaves had lower parasite loads. By decreasing the number of parasites such as mites, the sparrows that add more wormwood leaves to their nest produce heavier and healthier chicks.”

Squirrel sleep secrets

Arctic ground squirrels are known as super hibernators because their bodies almost entirely shut down for as much as eight months of the year. They go without food and water and breathe just once per minute, yet are resilient to muscle loss and long-term cellular damage.

Now researchers led by the University of Alaska Fairbanks have discovered one of their secrets: they can recycle their body’s nutrients.

Over two years, Sarah Rice and colleagues monitored squirrels in a laboratory, revealing that as their muscles slowly break down in temperatures just above freezing, they can convert the free nitrogen they are creating into amino acids, which can then be used to synthesise protein in tissues such as lungs, kidneys and skeletal muscle.

The researchers say their findings, published in the journal Nature Metabolism, complement previous research that suggested hibernators recycle urea, a waste product excreted in urine.

Scientists had theorised that those animals also recycle nitrogen to retain their body tissue during extreme fasting, and the new study confirms this in real time on a metabolic scale.

Learning more about the biochemistry of hibernation could contribute to a variety of potential medical treatments for humans, including the prevention of muscle loss in cancer patients and the elderly.