Latest news with #PNAS
Yahoo
3 days ago
- Science
- Yahoo
3,000 Feet Beneath the Ocean, Scientists Found Spiders With a Hidden Superpower
Here's what you'll learn when you read this story: In 2023, scientists from the Occidental College of Los Angeles collected 36 specimens of sea spider living near methane seeps along the Pacific Coast from California to Alaska. Upon examining the arachnid-like creatures, they discovered that these deep sea species form a symbiotic relationship with methylotrophic bacteria, which provide a food source in the pitch dark aphotic zone. This new study paints a more complete picture of how the deep sea helps keep methane (a potent greenhouse gas) from escaping into the atmosphere. When you live in the ocean's aphotic zone, where absolute darkness reigns, you need some creative solutions to some pretty existential questions. Chief among them: what are you going to eat? For a variety of ocean floor-dwelling species, including mussels, worms, and sponges, that answer lies with chemosynthetic bacteria—organisms that flourish around methane seeps where the gas escapes the Earth's crust. A new study shows that three species of the sea spider genus Sericosura also demonstrate a similar ability, which helps explain why these spindly-legged organisms are found in such abundance near methane seeps. The results of the study were published in the journal Proceedings of the National Academy of Sciences (PNAS). Despite the name, sea spiders aren't actually spiders (though, that'll likely be of little comfort to an arachnophobe). Although they look remarkably similar, sea spiders have a thinner cephalothorax than their eight-legged land-based lookalikes, and their legs tend to have more joints. Oh, and they also live in the deep ocean—one of biology's true final frontiers of scientific inquiry. This hard-to-reach ecosystem is why many aspects of their lives remain a mystery. 'Our study aimed to examine the ways in which often overlooked animals might take advantage of novel energy sources, such as methane,' Shana Goffredi, the senior author of the study from the Occidental College of Los Angeles, said in a press statement. 'While the deep sea feels far away, all organisms are interconnected, and the processes in one ecosystem affect another.' In 2023, Goffredi—along with two students, including Bianca Dal Bó—embarked on a two-week research expedition on the R/V Atlantis to study these creatures in their deep-sea habitats. With the help of a piloted submersible named Alvin, they examined and collected sea spider specimens located 1,000 meters (3,280 feet) below the ocean surface from the Del Mar and Palos Verdes seeps in California and the Sanak seep in Alaska. Of the 36 specimens recovered, three of the spiders represented entirely new species. 'I had seen animal samples in preservatives in the lab for so long, so it was beautiful to finally see them moving around in their natural habitat,' Dal Bó said in a press statement. 'It made me feel all the more connected to my project and these fascinating ecosystems.' While performing experiments on board, Goffredi and Dal Bó incubated the sea spiders in seawater with methanol and a heavy isotope of methane. Because this isotope is rare in nature, the researchers could track its impact on the sea spiders, including if it was ingested. They found that methylotrophic bacteria located on the sea spiders' exoskeletons served as a source of a food. 'Evidence from tissue isotopic analysis, microbiome sequencing, and live-animal incubations followed by 13C-methane isotope probing confirms active incorporation of methane-derived carbon into spider tissues,' the authors wrote. 'This research highlights a previously unknown interaction between an animal lineage and chemically fueled microbes, introducing another symbiotic pathway for direct microbial transfer of methane carbon into animal biomass in the deep sea.' This transfer of methane carbon into animal biomass is particularly important for scientists to understand, as methane is one of the most potent greenhouse gases. Sea spiders—with the help of other deep ocean-dwelling animals—are doing their part to keep these gases locked away in the ocean, so they don't reach the atmosphere and exacerbate the ongoing climate crisis. 'While the deep sea feels really far away, all organisms are interconnected,' Goffredi told CNN. 'Even though they're small, these animals have a big impact in that environment. We can't ever hope to sustainably (use) the oceans if we don't really understand the oceans.' You Might Also Like The Do's and Don'ts of Using Painter's Tape The Best Portable BBQ Grills for Cooking Anywhere Can a Smart Watch Prolong Your Life?
Times
4 days ago
- Science
- Times
Scientists create fertile mice with two fathers for first time
Scientists have created fertile mice from male genetic material alone, a breakthrough that could one day open the door to human babies who inherit their genes from two fathers. The experiment, led by Professor Yanchang Wei at Shanghai Jiao Tong University in China, marks a milestone in the quest to overcome the biological barriers to same-sex reproduction. The research, published in the journal PNAS, involved inserting DNA from two sperm cells into an egg that had been emptied of its nucleus. This resulted in an androgenetic embryo — one that contains only male genetic material — which was then implanted into the uterus of a surrogate mother mouse. In mammals androgenetic embryos typically fail early in development due to a phenomenon known as genomic imprinting. Roughly speaking, this refers to how certain genes are turned on or off depending on whether they came from the mother or father, via chemical modifications or 'epigenetic tags' that are attached to their DNA. Wei and his colleagues overcame this by using an editing technique to 'reprogramme' seven regions of the DNA of one of the sperm cells placed inside the egg. Epigenetic tags were altered to restore the genetic balance normally achieved by having input from a male and a female. Out of 259 embryos implanted into female mice, only two male pups survived to adulthood. Though the success rate was low, both males went on to have healthy offspring with female partners — the first time this has been achieved with two-father animals. The science is still in its early stages and there is no prospect of human babies being born with two fathers in the near future. However, the implications may be profound. • 'Motherless' mice created from embryos with only male genes Unlike some previous attempts to produce same-sex mammalian offspring, the technique used involved editing only the epigenetic features that control the activity levels of genes, rather than the genes themselves. This may makes it more useful for future clinical applications. However, the extremely low success rate of the technique used in the study would require an unacceptable number of eggs and surrogate mothers. One reason for the low success rate is that combining two sperm increases the odds of producing embryos with two Y chromosomes, which cannot develop. The epigenetic reprogramming also only worked fully in a fraction of the embryos. In 2004, Japanese researchers created a female mouse from two mothers — a breakthrough at the time. But producing viable offspring from two sperm has proven far more complicated, requiring a deeper understanding of imprinting. If the technique were ever adapted for use in humans, such children would technically still have a 'third parent' in the egg donor, whose mitochondrial DNA would remain in the embryo. However, they would inherit their nuclear DNA, which contains the vast majority of their genetic code, from two men.
Daily Mail
4 days ago
- Science
- Daily Mail
First mouse with two biological FATHERS has its own babies - in breakthrough that could pave the way for gay men to have children
For the first time, mice born to two fathers have grown up and produced offspring, scientists in China have revealed. The researchers at Shanghai Jiao Tong University managed to insert two sperm cells - one from each father - into a mouse egg whose nucleus had been removed. A gene editing technique was then used to reprogram parts of the sperm DNA to allow an embryo to develop – a process called androgenesis. The embryo, featuring the genetic material from two fathers, was transferred to a female womb and allowed to grow to term. Finally, the resulting offspring (male) managed to grow to adulthood and become a parent after mating conventionally with a female. In their lab experiments, the researchers managed to successfully demonstrate the method twice – birthing two fertile male mice, both with two fathers. The promising breakthrough could pave the way for two gay men to have a child of their own who can also go on to have a family. However, experts have cautioned that there is still a way to go before any such procedures are attempted in humans. 'In this study, we report the generation of fertile androgenetic mice,' the Chinese experts say in their paper, published in the journal PNAS. 'Our findings, together with previous achievements of uniparental reproduction in mammals, support previous speculation that genomic imprinting is the fundamental barrier to the full-term development of uniparental mammalian embryos.' Experts caution that we are not ready to start such experiments in humans, which could be deeply unethical. Christophe Galichet, research operations manager at the Sainsbury Wellcome Centre in London, points out that the success rate of the experiments was very low. Of 259 mice embryos that were transferred to female mice, just two survived, grew to adulthood and then fathered their own offspring. 'This research on generating offspring from same-sex parents is promising,' Galichet, who was not involved with the experiments, told New Scientist. '[But] it is unthinkable to translate it to humans due to the large number of eggs required, the high number of surrogate women needed and the low success rate.' Today, gay couples who want to have children usually rely on a surrogate mother or father to bring a child into the world. How did the scientists do it? Experts took sperm from two male mice and injected it into an immature egg cell with its genetic material removed (known as enucleation) Gene editing was then used to reprogram seven parts of the sperm DNA to allow an embryo to develop The embryo, featuring the genetic material from two fathers, was transferred to a female womb and allowed to grow to term The offspring grew to adulthood and became a parent after mating with a member of the opposite sex These offspring appeared normal in terms of size, weight, appearance Unlike with a pair of heterosexual parents, this means that one of the couple is not actually related to the child. So it's long been a dream for gay couples to raise a child who has genetic material from both fathers (or both mothers). Back in 2023, researchers revealed they'd been able to create mice from two biological fathers for the first time. Because mice are actually genetically very similar to us, the promising results hinted the feat could be replicable in humans. But even if a human child could be birthed from two fathers, it potentially threw a huge ethical quandary into the mix: What if that human child is not able to have children of their own through normal conception when they reach adulthood? Fortunately, these new experiments suggest this might not be an issue. The human related to both of his or her fathers would grow up and be able to have a family of their own, the results suggest. During heterosexual reproduction, genetic material from a male carried by the sperm combines with genetic material from a female contained in the egg, or ovum. When this happens, a group of genes called 'homologous chromosomes' from the mother come together with those from the father and combine in a process called 'crossing over'. But when both sets of homologous chromosomes come from either two males or two females, the genes don't copy over properly, leading to 'imprinting abnormalities' and developmental defects. That's why the researchers had to turn to gene editing, which makes tweaks in the DNA, and target genes responsible for imprinting. Researchers are also considering this approach in larger animals like monkeys – but the technological hurdles will be significantly larger. Dr Helen O'Neill, molecular geneticist at the University College London, called the new work a 'major step forward'. 'It confirms that genomic imprinting is the main barrier to uniparental reproduction in mammals and shows it can be overcome,' she told New Scientist. Earlier this year, another Chinese team got mice with two fathers to grow to adulthood by editing 20 different genes in their stem cells, but the rodents weren't fertile. What is gene editing? Genome editing enables scientists to make changes to DNA, leading to changes in physical traits. Scientists use different technologies to do this. These technologies act like scissors, cutting the DNA at a specific spot. Then scientists can remove, add, or replace the DNA where it was cut. The first genome editing technologies were developed in the late 1900s. More recently, a new genome editing tool called CRISPR, invented in 2009, has made it easier than ever to edit DNA. The acronym stands for 'Clustered Regularly Inter-Spaced Palindromic Repeats'. The technique involves a DNA cutting enzyme and a small tag which tells the enzyme where to cut. By editing this tag, scientists are able to target the enzyme to specific regions of DNA and make precise cuts, wherever they like. It has been used to 'silence' genes - effectively switching them off. When cellular machinery repairs the DNA break, it removes a small snip of DNA. In this way, researchers can precisely turn off specific genes in the genome.
Yahoo
5 days ago
- Health
- Yahoo
Georgia attractive to 'dark' personalities, study suggests
The Brief A new study has found a direct link between adverse societal conditions and the dark personalities who live among them. People with a "dark factor of personality" are associated with behaviors like aggression, cheating, narcissism, exploitation and more. Those "dark" traits come with "high social costs," researchers say. Researchers trying to understand "dark" personality traits like narcissism, psychopathy and sadism have found a direct link between those characteristics and places with high corruption, poverty and violence. The study, conducted by three researchers from the University of Copenhagen and published in the scientific journal PNAS, used data from 1.8 million people in 183 countries, including 144,000 people in the United States. What they found is a moderate correlation between adverse social conditions and the dark personalities of people who live among them. Although the proven link between society and personality is considered moderate, the impact can be profound, researchers concluded. RELATED: These are the happiest cities in America, according to a new study Big picture view According to the Society for Personality and Social Psychology, the dark factor of personality is defined as "the tendency to maximize one's individual utility while disregarding, accepting, or malevolently provoking disutility for others," and "hold beliefs that, in their minds, justify their anti-social behavior." RELATED: Luke Combs admits his struggle with 'obscure' mental health disorder can be 'all-consuming' What they're saying "Aversive personality traits are associated with behaviours such as aggression, cheating, and exploitation – and thus with high social costs," Ingo Zettler, one of the study's authors, said in a news release. "In societies where rules are broken without consequences and where the conditions for many citizens are bad, individuals perceive and learn that one should actually think of oneself first," he continued. "Our findings substantiate that personality is not just something we are born with, but also shaped by the society we grew up and live in." Local perspective Charts from the study show the following states have the most adverse societal conditions: Louisiana Mississippi New Mexico Alabama Texas New York New Hampshire Utah Minnesota Vermont Wisconsin Iowa Nevada New York Texas South Dakota Alabama Georgia Vermont Utah Maine Oregon Alaska New Hampshire What you can do Researchers said governments that reduce corruption and inequality could "not only create better living conditions just now – they may also contribute to mitigating aversive personality levels among citizens in the future." The Source This report includes information from the PNAS scientific journal and the University of Copenhagen.
Yahoo
5 days ago
- Health
- Yahoo
These states are most attractive to "dark" personalities, study suggests
The Brief A new study has found a direct link between adverse societal conditions and the dark personalities who live among them. People with a "dark factor of personality" are associated with behaviors like aggression, cheating, narcissism, exploitation and more. Those "dark" traits come with "high social costs," researchers say. Researchers trying to understand "dark" personality traits like narcissism, psychopathy and sadism have found a direct link between those characteristics and places with high corruption, poverty and violence. The study, conducted by three researchers from the University of Copenhagen and published in the scientific journal PNAS, used data from 1.8 million people in 183 countries, including 144,000 people in the United States. What they found is a moderate correlation between adverse social conditions and the dark personalities of people who live among them. Although the proven link between society and personality is considered moderate, the impact can be profound, researchers concluded. RELATED: These are the happiest cities in America, according to a new study Big picture view According to the Society for Personality and Social Psychology, the dark factor of personality is defined as "the tendency to maximize one's individual utility while disregarding, accepting, or malevolently provoking disutility for others," and "hold beliefs that, in their minds, justify their anti-social behavior." RELATED: Luke Combs admits his struggle with 'obscure' mental health disorder can be 'all-consuming' What they're saying "Aversive personality traits are associated with behaviours such as aggression, cheating, and exploitation – and thus with high social costs," Ingo Zettler, one of the study's authors, said in a news release. "In societies where rules are broken without consequences and where the conditions for many citizens are bad, individuals perceive and learn that one should actually think of oneself first," he continued. "Our findings substantiate that personality is not just something we are born with, but also shaped by the society we grew up and live in." Local perspective Charts from the study show the following states have the most adverse societal conditions: Louisiana Mississippi New Mexico Alabama Texas New York New Hampshire Utah Minnesota Vermont Wisconsin Iowa Nevada New York Texas South Dakota Alabama Georgia Vermont Utah Maine Oregon Alaska New Hampshire What you can do Researchers said governments that reduce corruption and inequality could "not only create better living conditions just now – they may also contribute to mitigating aversive personality levels among citizens in the future." The Source This report includes information from the PNAS scientific journal and the University of Copenhagen.
