Rough-nosed horned lizards, or Ceratophora aspera, are small lizards that live in Sri Lankan rainforests and aren’t found anywhere else in the world. Characterized by the prominent horn in males, rough-nosed horned lizards live in moist, humid microhabitats in rainforests and palm groves. These lizards are particularly well-suited to understand the consequences of rainforest habitat destruction, climate change and the pet trade, as they are found throughout the lowland rainforests of Southwestern Sri Lanka. By analyzing the certain types of mutations in the genome of these lizards, the team was able to determine how geography and historical events impact the distribution of the remaining wild populations of rough-nosed horned lizards. Recent UW graduate Shanelle Wikramanayake led the study as part of her undergraduate work, and is now completing her master’s degree at California State University, Northridge.

The team acquired DNA from the rough-nosed horned lizards by a catch-and-release approach of capturing wild lizards and taking tissue samples from the tips of their tails before releasing them back to the wild, which minimizes stress to the animals. Samples were taken across eight forests representing four forest groups from July through September 2018 and 2019, respectively. The remaining tissue samples will be housed along with photos of the lizards at the Department of Zoology and Environment Sciences at the University of Colombo. In addition, the DNA analysis from the team’s work is also available online, where the samples and analysis are available for other researchers around the globe to study.

In addition to habitat destruction, nonnative species like cats and chickens eat these lizards, causing further harm to them and other prey animals. The team recommends a conservation strategy that considers the population structure, history and ecology of rough-nosed horned lizards to preserve genetic diversity.

The results from the DNA analysis found rough-nosed horned lizards are separated by distance into four forest groups: Southern Lowlands, Sabaragamuwa Hills, Central Highlands and Kithulgala. With the Sri Lankan government pledging to restore rainforest habitats, the results from the study can help inform guidelines for forest landscape restoration. For example, the similarities in populations and close geographic proximity between the lizards living in the Hiyare and Kottawa forest reserves in the Southern Lowlands forest group is a great candidate for habitat restoration. The two populations could be reconnected, increasing the chances for interbreeding, which could result in a stronger gene pool for future generations and less vulnerability to extinction.

“I hope this study brings attention to the unique and obscure biodiversity in the rainforests of Sri Lanka that require urgent conservation action,” said Wikramanayake. “It’s important to consider the genetic diversity in populations across their range when looking at conservation planning and strategies. This principle should also be considered in other forest ecosystems, where conservationists are planning restoration and habitat connectivity at landscape scales.”

In addition to these lizards, the researchers are currently considering extending this work to other animals and other regions of Sri Lanka of high conservation value. In Sri Lanka, approximately 14% of mammals, 6.5% of birds, 75% of reptiles and 29% of flowering plant species aren’t found anywhere else in the world. The methods of DNA analysis in this study not only inform conservation planning in Sri Lanka, but they also can be applied to species living in other rainforests that are at risk, including Madagascar, Borneo and the Amazon.

“I am proud and impressed with the hard work and passion that Shanelle Wikramanayake put into her project,” said Adam Leaché, UW biology professor and Burke Museum curator of herpetology and genetic resources. “The Burke Museum is lucky to recruit such amazing undergraduates.”

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Materials provided by University of Washington. Original written by Andrea Godinez. Note: Content may be edited for style and length.

What effect did the heat wave of summer 2020 have in Siberia? In a study led by the University of Bonn (Germany), geologists compared the spatial and temporal distribution of methane concentrations in the air of northern Siberia with geological maps. The result: the methane concentrations in the air after last year’s heat wave indicate that increased gas emissions came from limestone formations. The study is published in the journal Proceedings of the National Academy of Sciences (PNAS).

Permanently frozen permafrost soils cover large areas of the northern hemisphere, especially in northern Asia and North America. If they thaw in a warming world, this can pose dangers, because CO₂ and methane are released during thawing — and amplify the anthropogenic greenhouse gas effect. “Methane is particularly dangerous here because its warming potential is many times higher than that of CO₂,” explains Prof. Dr. Nikolaus Froitzheim from the Institute of Geosciences at the University of Bonn. Pessimists therefore already spoke of an imminent “methane bomb.” However, most previous projections showed that greenhouse gases from thawing permafrost will contribute “only” about 0.2 degrees Celsius to global warming by 2100. This assumption has now been challenged by a new study by Nikolaus Froitzheim and his colleagues Jaroslaw Majka (Krakow/Uppsala) and Dmitry Zastrozhnov (St. Petersburg).

Most previous studies only dealt with emissions from the decay of plant and animal remains in the permafrost soils themselves. In their current study, researchers led by Nikolaus Froitzheim made a comparison between methane concentrations in Siberian air, determined by satellite-based spectroscopy, and geological maps. They found significantly elevated concentrations in two areas of northern Siberia — the Taymyr Fold Belt and the rim of the Siberian Platform. What is striking about these two elongated areas is that the bedrock there is formed by limestone formations from the Paleozoic era (the period from about 541 million years ago to about 251.9 million years ago).

In both areas, the elevated concentrations appeared during the extreme heatwave in summer 2020 and persisted for months after. But how did the additional methane occur in the first place? “The soil formations in the observed areas are very thin to nonexistent, making methane emission from the decay of organic soil matter unlikely,” says Niko Froitzheim. He and his colleagues therefore suggest that fracture and cave systems in the limestone, which had been clogged by a mixture of ice and gas hydrate, became permeable upon warming. “As a result, natural gas being mainly methane from reservoirs within and below the permafrost can reach the Earth’s surface,” he says.

The scientists now plan to investigate this hypothesis by measurements and model calculations to find out how much and how fast natural gas may be released. “The estimated amounts of natural gas in the subsurface of North Siberia are huge. When parts of this will be added to the atmosphere upon thawing of the permafrost, this could have dramatic impacts on the already overheated global climate,” emphasizes Niko Froitzheim.

The universities of Bonn, Uppsala and AGH Krakow as well as the Karpinsky Russian Geological Research Institute in St. Petersburg were involved in the study.

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Materials provided by University of Bonn. Note: Content may be edited for style and length.

“This star is moving so fast that it’s almost certainly leaving the galaxy…[it’s] moving almost two million miles an hour,” says JJ Hermes, Boston University College of Arts & Sciences assistant professor of astronomy. But why is this flying object speeding out of the Milky Way? Because it’s a piece of shrapnel from a past explosion — a cosmic event known as a supernova — that’s still being propelled forward.

“To have gone through partial detonation and still survive is very cool and unique, and it’s only in the last few years that we’ve started to think this kind of star could exist,” says Odelia Putterman, a former BU student who has worked in Hermes’ lab.

In a new paper published in The Astrophysical Journal Letters, Hermes and Putterman uncover new observations about this leftover “star shrapnel” that gives insight to other stars with similar catastrophic pasts.

Putterman and Hermes analyzed data from NASA’s Hubble Space Telescope and Transiting Exoplanet Survey Satellite (TESS), which surveys the sky and collects light information on stars near and far. By looking at various kinds of light data from both telescopes, the researchers and their collaborators found that LP 40?365 is not only being hurled out of the galaxy, but based on the brightness patterns in the data, is also rotating on its way out.

“The star is basically being slingshotted from the explosion, and we’re [observing] its rotation on its way out,” says Putterman, who is second author on the paper.

“We dug a little deeper to figure out why that star [was repeatedly] getting brighter and fainter, and the simplest explanation is that we’re seeing something at [its] surface rotate in and out of view every nine hours,” suggesting its rotation rate, Hermes says. All stars rotate — even our sun slowly rotates on its axis every 27 days. But for a star fragment that’s survived a supernova, nine hours is considered relatively slow.

Supernovas occur when a white dwarf gets too massive to support itself, eventually triggering a cosmic detonation of energy. Finding the rotation rate of a star like LP 40?365 after a supernova can lend clues into the original two-star system it came from. It’s common in the universe for stars to come in close pairs, including white dwarfs, which are highly dense stars that form toward the end of a star’s life. If one white dwarf gives too much mass to the other, the star being dumped on can self-destruct, resulting in a supernova. Supernovas are commonplace in the galaxy and can happen in many different ways, according to the researchers, but they are usually very hard to see. This makes it hard to know which star did the imploding and which star dumped too much mass onto its star partner.

Based on LP 40?365’s relatively slow rotation rate, Hermes and Putterman feel more confident that it is shrapnel from the star that self-destructed after being fed too much mass by its partner, when they were once orbiting each other at high speed. Because the stars were orbiting each other so quickly and closely, the explosion slingshotted both stars, and now we only see LP 40-365.

“This [paper] adds one more layer of knowledge into what role these stars played when the supernova occurred,” and what can happen after the explosion, Putterman says. “By understanding what’s happening with this particular star, we can start to understand what’s happening with many other similar stars that came from a similar situation.”

“These are very weird stars,” Hermes says. Stars like LP 40-365 are not only some of the fastest stars known to astronomers, but also the most metal-rich stars ever detected. Stars like our sun are composed of helium and hydrogen, but a star that has survived a supernova is primarily composed of metal material, because “what we’re seeing are the by-products of violent nuclear reactions that happen when a star blows itself up,” Hermes says, making star shrapnel like this especially fascinating to study.

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Materials provided by Boston University. Original written by Jessica Colarossi. Note: Content may be edited for style and length.