Tag: animals

Categories
Life Style

The origins of bioluminescence in animals date back over half a billion years

[ad_1]

Hello Nature readers, would you like to get this Briefing in your inbox free every day? Sign up here.

A magnificent coral Iridogorgia magnispiralis, a deep-sea octocorals that are known to be bioluminescent.

A bioluminescent octocoral, Iridogorgia magnispiralis.Credit: NOAA Office of Ocean Exploration and Research, Deepwater Wonders of Wake

An ancient group of glowing corals pushes back the origin of bioluminescence in animals to more than half a billion years ago. “We had no idea it was going to be this old,” says evolutionary marine biologist and study co-author Danielle DeLeo. Tiny crustaceans that lived around 270 million years ago were previously thought to be the earliest glowing animals. Genetic analysis and computer modelling revealed that octocorals probably evolved the ability to make light much earlier, around the time when the first animals developed eyes.

Nature | 4 min read

Reference: Proceedings of the Royal Society B paper

A virulent strain of the monkeypox virus might have gained the ability to spread through sexual contact. The strain, called clade Ib, has caused a cluster of infections in a conflict-ridden region of the Democratic Republic of the Congo (DRC). This isn’t the first time scientists have warned that the monkeypox virus could become sexually transmissible: similar warnings during a 2017 outbreak in Nigeria were largely ignored. The strain responsible, clade II, is less lethal than clade Ib, but ultimately caused an ongoing global outbreak that has infected more than 94,000 people and killed more than 180. “The DRC is surrounded by nine other countries — we’re playing with fire here,” says virologist Nicaise Ndembi.

Nature | 5 min read

Reference: medRxiv preprint (not peer reviewed)

The World Health Organization (WHO) has changed how it classifies airborne pathogens. It has removed the distinction between transmission by smaller virus-containing ‘aerosol’ particles and spread through larger ‘droplets’. The division, which some researchers argue was unscientific, justified WHO’s March 2020 assertion that SARS-CoV-2, the virus behind the COVID-19 pandemic, was not airborne. Under the new definition, SARS-CoV-2 would be recognized as spreading ‘through the air’ — although some scientists feel this term is less clear than ‘airborne’. “I’m not saying everybody is happy, and not everybody agrees on every word in the document, but at least people have agreed this is a baseline terminology,” says WHO chief scientist Jeremy Farrar.

Nature | 6 min read

Reference: WHO technical report

Features & opinion

The development of lethal autonomous weapons, such as AI-equipped drones, is on the rise. “The technical capability for a system to find a human being and kill them is much easier than to develop a self-driving car,” says computer scientist and campaigner against AI weapons Stuart Russell. Some argue that accurate AI weapons could reduce collateral damage while helping vulnerable nations to defend themselves. At the same time, observers are concerned that passing targeting decisions to an algorithm could lead to catastrophic mistakes. The United Nations will discuss AI weapons at a meeting later this year — potentially a first step towards controlling the new threat.

Nature | 11 min read

In early April, the European Court of Human Rights ruled in favour of a group of more than 2,500 Swiss female activists aged 64 or over who argued that Switzerland was doing too little to protect them as a group particularly vulnerable to health effects stemming from climate change. “This marks the first time that an international human-rights court has linked protection of human rights with duties to mitigate global warming, clarifying once and for all that climate law and policy do not operate in a human-rights vacuum,” says legal scholar Charlotte Blattner, who advised the court. “The ruling is bound to alter the course of climate protection around the world.”

Nature | 5 min read

When US scientists needed a place to test the first birth-control pill, they looked to Puerto Rico. But many of the working-class women who took the pill were unaware that they were part of a clinical trial. Debilitating side effects were dismissed as psychosomatic. And when the final product came onto the market, it was too expensive for women like them to afford. The play Las Borinqueñas revisits this complicated history. “It’s a long-overdue tribute and, most importantly, a reminder to remain vigilant against abuse and disrespect in studies involving human participants,” writes Nature reporter Mariana Lenharo in her review.

Nature | 7 min read

Image of the week

A person holding a pole with a hook leaning out of a orange metal basket that is being lowered by crane towards a broken ice sheet to retrieve equipment below the icy surface

Winning image: Glaciologist Richard Jones captured the moment a crew member on RV Polarstern prepared to rescue a measuring device trapped in ice.Credit: Richard Jones

This image, taken on top of the icebreaker research vessel Polarstern, shows the delicate process of retrieving an ocean-monitoring instrument called a CTD (short for conductivity, temperature, depth) that had become trapped under sea ice off the coast of northeastern Greenland. CTDs, which are anchored to the sea floor, measure how properties such as salinity and temperature vary with depth. The photo is the winner of Nature’s 2024 Working Scientist photography competition. See the rest of the winning images from the competition here.

Yesterday we told you that NASA had reconnected with its spacecraft Voyager 1, the first human-made object to leave the Solar System. But was it really the first? A reader question sparked a debate in the newsroom about whether that accolade should rightfully go to Pioneer 10.

A lot depends on how we define the edge of the Solar System, explains Nature reporter Sumeet Kulkarni. “But I think it’s safe to say Voyager 1 left it first,” he says. The craft overtook Pioneer 10 in 1998, and left the heliosphere — the reach of the Sun’s influence — in 2013, by which time it was travelling much faster than Pioneer 10.

Let us know how your journeys are progressing — and any other feedback on this newsletter — at [email protected].

Thanks for reading,

Flora Graham, senior editor, Nature Briefing

With contributions by Katrina Krämer and Sarah Tomlin

Want more? Sign up to our other free Nature Briefing newsletters:

• Nature Briefing: Microbiology — the most abundant living entities on our planet — microorganisms — and the role they play in health, the environment and food systems.

• Nature Briefing: Anthropocene — climate change, biodiversity, sustainability and geoengineering

• Nature Briefing: AI & Robotics — 100% written by humans, of course

• Nature Briefing: Cancer — a weekly newsletter written with cancer researchers in mind

• Nature Briefing: Translational Research — covers biotechnology, drug discovery and pharma

[ad_2]

Source Article Link

Categories
Life Style

First glowing animals lit up the oceans half a billion years ago

[ad_1]

A magnificent coral Iridogorgia magnispiralis, a deep-sea octocorals that are known to be bioluminescent.

A bioluminescent octocoral, Iridogorgia magnispiralis.Credit: NOAA Office of Ocean Exploration and Research, Deepwater Wonders of Wake

Some 540 million years ago, an ancient group of corals developed the ability to make its own light1.

Scientists have previously found that bioluminescence is an ancient trait — with one group of tiny crustaceans first making their own light an estimated 267 million years ago. But this new finding pushes back the origins of bioluminescence even further by around 270 million years.

“We had no idea it was going to be this old,” says Danielle DeLeo, an evolutionary marine biologist at Florida International University in Miami, who led the study, which was published on 24 April in Proceedings of the Royal Society B. “The fact that this trait has been retained for hundreds of millions of years really tells us that it is conferring some type of fitness advantage.”

Bioluminescence has evolved independently at least 100 times in animals and other organisms. Some glowing species, such as fireflies, use their light to communicate in the darkness. Other animals, including anglerfish, use it as a lure to attract prey, or to scare away predators.

However, it’s not always clear why bioluminescence evolved. Take octocorals. These soft-bodied organisms are found in both shallow water and the deep ocean, and produce an enzyme called luciferase to break down a chemical to make light. But whether glowing octocorals use their light to attract zooplankton as prey or for some other purpose is unclear.

First light

Searching for answers, DeLeo and her colleagues analysed a large data set of genetic sequences and the sparse octocoral fossil record to reconstruct the animals’ evolutionary history. They then used a computer model to determine how likely it was that ancestral species were bioluminescent.

The model revealed that the common ancestor of all octocorals — which lived around 540 million years ago — was probably bioluminescent. The finding suggests that luciferase-based biofluorescence evolved early and was lost by non-bioluminescent descendants of ancient glowing octocorals.

The study shows that bioluminescence has been around since at least the Cambrian period (around 540 million to 485 million years ago), when the first animal species developed eyes. That’s surprising, says evolutionary biologist Todd Oakley, at the University of California, Santa Barbara, because bioluminescence is a trait that “tends to blink on and off” across evolutionary time.

Luciferase is just one way animals make light. Other organisms use different chemistry to get their telltale glow. In the case of octocorals, the luciferase system could have evolved for the production of an antioxidant, says DeLeo. Later, the light-generating aspect of the reaction would have become useful for communication.

In any case, the deep origin of bioluminescence suggests that it could be one of the oldest forms of communication on Earth, she says. “If you’re producing light — whether or not it’s intentional — you are signalling other animals,” she says. “Like, ‘Hey! I’m over here!”

[ad_2]

Source Article Link

Categories
Computers

How Will the Solar Eclipse Affect Animals? NASA Needs Your Help to Find Out

[ad_1]

In other anecdotes, onlookers have reported birds that stop singing, crickets that stopped chirping, or bees that return to their hive, reduce their foraging, or suspend their flight during total darkness. But there are also studies that deny that some of these behaviors occur or can be attributed to the eclipse.

Therefore, NASA scientists plan not only to systematize observations but also to document what people hear and see under the shadow of the moon.

“The Great North American Eclipse”

NASA has created the Eclipse Soundscapes citizen science project to collect the experiences of volunteers. It was inspired by a study conducted nearly 100 years ago by William M. Wheeler and a team of collaborators. At that time, the Boston Natural History Society invited citizens, park rangers, and naturalists to report on the activities of birds, mammals, insects, reptiles, and fish during the summer eclipse of 1932. They collected nearly 500 reports. In their final report they note that some animals exhibited nocturnal behaviors such as returning to their nests and hives or making nighttime vocalizations.

The current NASA study will add observations made during the annular solar eclipse of October 14, 2023 and the total solar eclipse of April 8. The latter will be visible first in Mexico in Mazatlan, then in Nazas, Torreon, Monclova, and Piedras Negras. These localities will be located directly in the umbra of the eclipse and, therefore, their inhabitants will perceive it as total. In nearby regions it will be experienced as a partial eclipse, with less darkness. It will then enter the United States through Texas, passing through Oklahoma, Arkansas, Missouri, Illinois, Kentucky, Kentucky, Indiana, Ohio, Pennsylvania, New York, Vermont, New Hampshire and Maine. Finally, it will travel across Canada from southern Ontario and continue through Quebec, New Brunswick, Prince Edward Island and Cape Breton. Astronomical estimates point to the Mexican port of Mazatlan as the best place to observe the 2024 event, which will experience totality at about 11:07 am local time.

Image may contain Animal Beak Bird Sparrow Nature Night Outdoors Finch Astronomy and Moon

A sparrow experiencing a partial solar eclipse in Jize Country, Hebei Province, China, June 21, 2020.Future Publishing/Getty Images

How You Can Help

In the United States, 30 million people live in the area where the eclipse will be perceived as total. If you add in the Mexican and Canadian public, the potential for collecting experiences is immense. That’s what NASA wants to take advantage of.

The project foresees several levels of volunteering: apprentice, observer, data collector, data analyst, and facilitator.

[ad_2]

Source Article Link

Categories
Politics

New study reveals insight into which animals are most vulnerable to extinction due to climate change

[ad_1]

In a new study, researchers have used the fossil record to better understand what factors make animals more vulnerable to extinction from climate change. The results could help to identify species most at risk today from human-driven climate change. The findings have been published today in the journal Science.

Past climate change (often caused by natural changes in greenhouse gases due to volcanic activity) has been responsible for countless species’ extinctions during the history of life on Earth. But, to date, it has not been clear what factors cause species to be more or less resilient to such change, and how the magnitude of climate change affects extinction risk.

Led by researchers at the University of Oxford, this new study sought to answer this question by analysing the fossil record for marine invertebrates (such as sea urchins, snails, and shellfish) over the past 485 million years. Marine invertebrates have a rich and well-studied fossil record, making it possible to identify when, and potentially why, species become extinct.

Using over 290,000 fossil records covering more than 9,200 genera, the researchers collated a dataset of key traits that may affect resilience to extinction, including traits not studied in depth previously, such as preferred temperature. This trait information was integrated with climate simulation data to develop a model to understand which factors were most important in determining the risk of extinction during climate change.

Key findings:

  • The authors found that species exposed to greater climate change were more likely to become extinct. In particular, species that experienced temperature changes of 7°C or more across geological stages were significantly more vulnerable to extinction.
  • The authors also found that species occupying climatic extremes (for instance in polar regions) were disproportionately vulnerable to extinction, and animals that could only live in a narrow range of temperatures (especially ranges less than 15°C) were significantly more likely to become extinct.
  • However, geographic range size was the strongest predictor of extinction risk. Species with larger geographic ranges were significantly less likely to go extinct. Body size was also important, with smaller-bodied species more likely to become extinct.
  • All of the traits studied had a cumulative impact on extinction risk. For instance, species with both small geographic ranges and narrow thermal ranges were even more susceptible to extinction than species that had only one of these traits.

Cooper Malanoski (Department of Earth Sciences, University of Oxford), first author of the study, said: ‘Our study revealed that geographic range was the strongest predictor of extinction risk for marine invertebrates, but that the magnitude of climate change is also an important predictor of extinction, which has implications for biodiversity today in the face of climate change.’

With current human-driven climate change already pushing many species up to and beyond the brink of extinction, these results could help identify the animals that are most at risk, and inform strategies to protect them.

Lead author Professor Erin Saupe (Department of Earth Sciences, University of Oxford) said: ‘The evidence from the geological past suggests that global biodiversity faces a harrowing future, given projected climate change estimates. In particular, our model suggests that species with restricted thermal ranges of less than 15°C, living in the poles or tropics, are likely to be at the greatest risk of extinction. However, if the localized climate change is large enough, it could lead to significant extinction globally, potentially pushing us closer to a sixth mass extinction.’

According to the research team, future work should explore how climate change interacts with other potential drivers of extinction, such as ocean acidification and anoxia (where seawater becomes depleted of oxygen).

The study also involved researchers from the School of Geographical Sciences, University of Bristol. Professor Dan Lunt, from the University of Bristol, said: ‘This study shows that over the course of Earth’s history, the extinction risk of marine life has been inextricably linked to climate change. This should act as a stark warning to humanity as we recklessly continue to cause climate change ourselves through burning fossil fuels.’

[ad_2]

Source Article Link