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Category: Biology

Ageing: How our ‘epigenetic clocks’ slow down as we get older

Ageing: How our ‘epigenetic clocks’ slow down as we get older

Monkey Business Images By Leonard Schalkwyk, University of Essex and Jonathan Mill, University of Exeter From the tap dancing 90-year-old to the 40-year-old who struggles to run a mile, we all know people who seem surprisingly young or old for their age. Scientists believe that it may be possible to distinguish between two types of age: biological age, a measure of how well the body functions, and chronological age, your age in years. Epigenetics, the science of how environmental factors…

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In untold numbers, animals are suffering and dying, and we are either partly or wholly responsible

In untold numbers, animals are suffering and dying, and we are either partly or wholly responsible

Jeff Sebo writes: At the time of writing, Australia is on fire. The fires have killed at least 25 humans and more than a billion animals. Animals such as koalas are especially at risk, since their normal response to threats – climbing to the tops of trees – leaves them vulnerable in the case of fire. As a result, an estimated 25,000 koalas have died and many more will die in the coming weeks. In 2018, Hurricane Florence swept through…

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How viruses secretly control the planet

How viruses secretly control the planet

Nala Rogers writes: Viruses control their hosts like puppets — and in the process, they may play important roles in Earth’s climate. The hosts in this case aren’t people or animals: They are bacteria. A growing body of research is revealing how viruses manipulate what bacteria eat and how they guide the chemical reactions that sustain life. When those changes happen to a lot of bacteria, the cumulative effects could potentially shape the composition and behavior of Earth’s oceans, soil…

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New evidence suggests, the default condition in plants is immortality

New evidence suggests, the default condition in plants is immortality

Erin Malsbury writes: Long-lived humans having nothing on trees. Some, like the Ginkgo biloba, can live more than 3000 years. Now, in the most comprehensive plant aging study to date, researchers have revealed the molecular mechanisms that allow the ginkgo—and perhaps other trees—to survive so long. The new study provides the first real genetic evidence for something scientists have long suspected: “The default condition in plants is immortality,” says Howard Thomas, a plant biologist from Aberystwyth University who was not…

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Could invisible aliens really exist among us? An astrobiologist explains

Could invisible aliens really exist among us? An astrobiologist explains

They probably won’t look anything like this. Martina Badini/Shutterstock By Samantha Rolfe, University of Hertfordshire Life is pretty easy to recognise. It moves, it grows, it eats, it excretes, it reproduces. Simple. In biology, researchers often use the acronym “MRSGREN” to describe it. It stands for movement, respiration, sensitivity, growth, reproduction, excretion and nutrition. But Helen Sharman, Britain’s first astronaut and a chemist at Imperial College London, recently said that alien lifeforms that are impossible to spot may be living…

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The knowledge of trees

The knowledge of trees

Sue Burke writes: The U.N. Climate Change Conference in Madrid opened on Dec. 2 by calling the climate crisis a “war against nature.” But trees have always been at war, fighting for their survival. While plants may seem passive in the environment, they can sense their environments, make decisions, and respond to threats—up to a point. Every autumn holds terrible perils for plants. While many trees drop their leaves every year, the decision of precisely when to do so is…

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A new study shows an animal’s lifespan is written in the DNA. For humans, it’s 38 years

A new study shows an animal’s lifespan is written in the DNA. For humans, it’s 38 years

A genetic “clock” lets scientists estimate how long extinct creatures lived. Wooly mammoths could expect around 60 years. Australian Museum By Benjamin Mayne, CSIRO Humans have a “natural” lifespan of around 38 years, according to a new method we have developed for estimating the lifespans of different species by analysing their DNA. Extrapolating from genetic studies of species with known lifespans, we found that the extinct woolly mammoth probably lived around 60 years and bowhead whales can expect to enjoy…

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Light pollution is key ‘bringer of insect apocalypse’

Light pollution is key ‘bringer of insect apocalypse’

The Guardian reports: Light pollution is a significant but overlooked driver of the rapid decline of insect populations, according to the most comprehensive review of the scientific evidence to date. Artificial light at night can affect every aspect of insects’ lives, the researchers said, from luring moths to their deaths around bulbs, to spotlighting insect prey for rats and toads, to obscuring the mating signals of fireflies. “We strongly believe artificial light at night – in combination with habitat loss,…

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A molecular connection between the brain and aging

A molecular connection between the brain and aging

Veronique Greenwood writes: A thousand seemingly insignificant things change as an organism ages. Beyond the obvious signs like graying hair and memory problems are myriad shifts both subtler and more consequential: Metabolic processes run less smoothly; neurons respond less swiftly; the replication of DNA grows faultier. But while bodies may seem to just gradually wear out, many researchers believe instead that aging is controlled at the cellular and biochemical level. They find evidence for this in the throng of biological…

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The scammy world of DNA test startups

The scammy world of DNA test startups

Futurism reports: In the spring of 2017, a college student named Mary spit into a tube and sent it to the DNA testing company Ancestry, which analyzed it and sent back a breakdown of her family history. But Mary wanted to know more. The human genome contains, in theory, an extraordinary wealth of pre-programmed information about who we are and who we might become: whether she was at risk for the same types of cancer that killed her parents, for…

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Genes from bacteria helped plants move to land

Genes from bacteria helped plants move to land

Carl Zimmer writes: If you’ve ever noticed a slimy film of algae on a rock, chances are you didn’t pay it much attention. But some of these overlooked species hold clues to one of the greatest mysteries of evolution, scientists have found: how plants arrived on land. On Thursday, researchers published the genomes of two algae that are among the closest known living relatives of land plants. They already had some of the key genes that plants would need to…

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The elephant-human relationship dates back into prehistory

The elephant-human relationship dates back into prehistory

Tim Flannery writes: In January 1962, on my sixth birthday, I was taken to Melbourne Zoo, where I rode an elephant. We children climbed a scaffold and perched on rough wooden benches atop the elephant’s back, where my fingers furtively reached for a feel of its wrinkled skin. A few months later, elephant rides were discontinued, for safety reasons, at most zoos in Australia, Europe, and the US. I was dimly aware of the danger involved in mounting such an…

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Birds that form surprisingly complex societies

Birds that form surprisingly complex societies

Natalie Parletta writes: The gregarious, small-brained vulturine guineafowl (Acryllium vulturinum) forms complex, multi-level societies, according to new research. Published in the journal Current Biology, it challenges previous notions that only animals with large brains – such as humans, primates, elephants, giraffes and dolphins – are capable of such social structures. Lead investigator Damien Farine, from the Max Planck Institute of Animal Behaviour in Konstanz, Germany, says he was curious to know how groups of animals resolve conflicts and make collective…

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Mapping the human oral microbiome

Mapping the human oral microbiome

In an interview with Knowable Magazine, Floyd Dewhirst says: We don’t really know the number of bacteria in an average mouth. But there are something like 1011 [100 billion] organisms per gram of plaque — so we’re looking at a large number. What people usually talk about is how many species are in there. The Human Oral Microbiome Project identified a little over 700 different species of bacteria. (There are also fungi and viruses.) About 400 of the 700 bacterial…

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New bird species arises from hybrids, as scientists watch

New bird species arises from hybrids, as scientists watch

Quanta Magazine reported (2017): It’s not every day that scientists observe a new species emerging in real time. Charles Darwin believed that speciation probably took place over hundreds if not thousands of generations, advancing far too gradually to be detected directly. The biologists who followed him have generally defaulted to a similar understanding and have relied on indirect clues, gleaned from genomes and fossils, to infer complex organisms’ evolutionary histories. Some of those clues suggest that interbreeding plays a larger…

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Inherited learning? It happens, but how is uncertain

Inherited learning? It happens, but how is uncertain

Viviane Callier writes: As a biological concept, the inheritance of acquired characteristics has had a wild roller coaster ride over the past two centuries. Championed by Jean-Baptiste Lamarck at the beginning of the 19th century, it soared to widespread popularity as a theory of inheritance and an explanation for evolution, enduring even after Charles Darwin published On the Origin of Species. Then experimental tests, the rise of Mendelian genetics, and the wealth of discoveries substantiating chromosomal DNA as the principal…

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