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Penguins May Find It Genetically Difficult to Survive Climate Change
The rise and fall of earth's temperatures over millions of years drives evolution by favoring those species that are able to adapt to changing conditions. Normally, this is a gradual change that shapes species over thousands or even millions of generations. By studying the fossil record, we can identify what kinds of plants and animals changed the quickest. Then there are penguins. Comparing living and fossil penguin species on the genetic level, it turns out that penguins have the lowest rate of evolutionary change of all bird types. That may be the price of becoming so well adapted to an extreme environment in Antarctica, but it doesn't bode well for the birds' futures. The history of penguin evolution tells us that they lost their ability to fly some 60 million years ago, before the polar ice sheets developed, which hints that they may have become trapped in an environment that became hostile, and they had to adapt or die out. Millions of years later, they are specialists, and their lack of ability to change may be deadly as the earth warms at a rapid pace. Read about the latest discoveries in penguin DNA at ScienceAlert. -via Damn Interesting(Image credit: Ben Tubby) #penguin #evolution #DNA
Why Do Humans Sleep Less than Other Primates?
Adult humans average about seven hours of sleep per day. By contrast, chimpanzee, one of our closest relatives, sleep 9.5 hours a day, and other primates sleep even longer. Why is that? Common sense might tell you that it's because of television, the internet, stress, artificial schedules, and lights. But studies show that non-industrial communities, even those without electricity, sleep about the same amount. There's something about being human that causes us to get less sleep than other primates. Some new studies give us a hypothesis and some caveats. It's possible that we evolved to operate on less sleep when we stopped living in trees. Animals that sleep on the ground are at a higher risk from predators, so our ancestors began sleeping in groups with someone keeping watch in shifts. That would also explain why humans have more flexible sleep patterns than other primates. The caveat is that we might not know as much about animal sleep patterns as we think we do. Some studies show that creatures who live in zoos and laboratories sleep more than those in the wild, although studies of how long wild animals sleep in their own environment are rather scarce. Read a lot more about the research into why humans sleep less than other primates at Smithsonian.(Image credit: Daniel Ramirez)#sleep #primate #evolution #naturalselection
The First Taste was Probably Sour
All animals can taste, and almost all animals have the same receptors for taste, those for sweet, sour, bitter, salty, and umami (also called savory). The interaction of these receptors help guide an animal to foods that are beneficial to them and away from foods that may be dangerous. Humans are a bit different in that we have learned to appreciate some flavors that animals would avoid, like some mild bitterness and sour foods. It's a good thing that we had brave taste-testers, and later scientists, to let us know what foods might kill us. Some animals have lost a taste sense they didn't need, like cats that cannot taste sweetness, but they still have the genes that mean they once could, back in their evolutionary line. Scientists are looking into the genetic records to find out how these tastes developed and why. It turns out that no vertebrates have ever lost the ability to taste sourness. It appears that the ability to detect sourness was useful even before animals began judging the quality of potential foods they encountered. What's really interesting is the reason why humans are attracted to sour flavors when other animals aren't. -via Damn Interesting#taste #flavor #evolution
What's Ahead for Human Evolution?
There are some people who believe that humans are no longer evolving, since we've developed civilization and science. When we study the mechanisms of natural selection, we learn how the pressure from predators made us fast runners, and those who had better immune systems were more likely to pass their genes on. But now we have protection in communities and vaccines against disease. While environmental pressures favor certain traits and spur evolution, we haven't moved completely away from the effects of natural selection. The pressures we have today are just different.For one thing, we now live longer. This is partly due to natural selection, and partly due to medical science. The very absence of the pressure to reproduce at young age, lest we die first, allows us to delay having children. This gives those who experience puberty and menopause at a later age a better shot at producing children who survive and carry on those traits. Yet since survival plays a smaller role in when and how much we reproduce, sexual selection plays a larger role. What people find attractive in each other and how we meet someone to reproduce with will affect what kinds of children will result. Real Clear Science looks at how human evolution worked in the past, and speculates on how changing conditions will affect the traits that will proliferate in humans of the future. -via Damn Interesting(Image credit: Tkgd2007)#evolution #humanevolution #naturalselection
Bacteria are Evolving to Consume Plastic
The earth has a way of changing and adapting to new conditions over millions of years. New species arise, fill ecological niches, and then evolve again when conditions change. There was a time in the earth's ancient past that an adaptation in trees caused pollution in the form of too much lignin. Eventually, a type of microorganism evolved that ate lignin and solved the problem, although it took many millions of years. Today the pollution is human-driven, and the world has too much plastic. Will something evolve that eats plastic? That's already happened. Scientist discovered a new bacterium they named Ideonella sakaiensis near a plastic recycling facility in Japan. I. sakaiensis manufactures an enzyme that breaks down the plastic called polyethylene terephthalate (PET) into organic molecules it can consume. Other bacteria with such talents have been identified since then. But we don't have tens of million of years to dispose of plastic. Mother Nature has all the time in the world, but in order to preserve life as we know it, scientists are growing these plastic-eating bacteria and boosting their PETase, which is what the novel enzyme was named. While we still need to reduce our plastic waste, having microbes that decompose it can't hurt. Or can it? When we encourage any species to evolve and thrive, we don't know what the long-term consequences will be. Read more about this research at Real Clear Science. (Image credit: Dying Regime) #bacteria #plastic #evolution
Meet Homo Bodoensis, a New Species that was the Direct Ancestor of Modern Humans
Paleoanthropologists often describe The Middle Pleistocene period as "the muddle in the middle '' because human evolution from this time is poorly understood and heavily debated. To try and uncover this mystery in our origins, researchers have recently named a new human ancestor species, Homo bodoensis.The new name is based on a skull found in Bodo D’ar, Ethiopia. The name is a result of the reassessment of existing fossils from Africa and Eurasia. The said fossils were previously attributed to those of the Homo heidelbergensis or Homo rhodesiensis. Based on new DNA evidence, the former was revealed to be early Neanderthal. The latter, on the other hand, remains poorly defined.Palaeoanthropologist Dr. Mirjana Roksandic hopes that this new name will "stick around for a long time," as new names "will live only if other researchers use it."More about this over at The University of Winnipeg.(Image Credit: Ettore Mazza)#Paleoanthropology #HumanEvolution #Evolution
This Ant Study Could Have Found A Clue To Why Human Brains Decreased in Size 3,000 Years Ago
Why are our brains smaller than our Pleistocene ancestors? Anthropologists have been scratching their heads about this phenomenon for years now, says Dr. Jeremy DeSilva. It is said that throughout evolution, the human brain dramatically increased in size. However, 3,000 years ago, something unexpected happened. The human suddenly shrank. A biological anthropologist, a behavioral ecologist, and an evolutionary neurobiologist decided to put their heads together to try and solve this mystery, and they just might have found a clue to this phenomenon. And they found this clue on the humble little ant. By studying models and patterns of worker ant brain size, structure, and energy use in some ant clades, the authors posit that the human brains decreased in size to conserve energy. Our increased reliance on collective intelligence and group decision-making through time may also be one of the reasons why our brains got smaller. Learn more about this study over at Frontiers Science News. (Image Credit: Pjt56/ Wikimedia Commons) #Anthropology #Ants #Evolution
How Might Animals Evolve in the Next Million Years?
Some scientists believe we are now in the beginning stages of a mass extinction event. The earth is losing species at an alarming rate, due to human activity and climate change. But the earth has already seen at least five mass extinction events in its history. While a large percentage of existing species died out each time, there were always survivors that adapted and evolved to live in a new kind of environment. While we are learning about the past, looking to the future can be quite interesting. Mandy Nguyen at Vox asked various scientists to indulge in some speculative biology and imagine how species may evolve into something new in the relatively distant future. First, they had to imagine which species will survive the earth's current woes, and the absence of the ones that won't, and how those absences will affect the ecosystem. Which species will fill the future gaps in the food chain? One must also imagine what challenges a post-extinction event environment will present to surviving animals. Another factor to consider is whether humans will be around a million years from now, or how long we will have been gone by then. Read about the possibilities of aquatic rats with flippers, predatory pigeons, and giant praying mantises, among other evolved animals, at Vox. -via Metafilter(Image credit: Amanda Northrop/Vox) #evolution #species #speculativebiology
Snowflake Yeast Evolved From Unicellular Organism into a Multicellular One in Just Two Years
Life on Earth is indeed an astounding phenomenon. Just imagine. A single cell keeps on dividing itself until it forms into something more complex — a multicellular being. This phenomenon of single-celled organisms transforming into multicellular organisms has happened at least 20 times throughout the history of life on Earth. However, with great complexity come great responsibility. Compared to single-celled organisms that only live to "eat and divide" over and over, multicellularity has much more processes and dangers.But how do single-celled life transition to multicellular life? That's what biologist William Ratcliff and his colleagues investigated for nearly a decade.Today, they reported that they have successfully transformed unicellular yeasts into complex multicellular clusters. These clusters are said to be visible to the naked eye.Learn more about their research over at Quanta Magazine.(Video Credit: Ratcliff Lab, Georgia Tech)#Unicellular #Multicellular #Evolution #Research
A Colony on Mars Could Speed Up Human Evolution
Changes in an environment will put pressure on whatever lives there to change and adapt over generations. On Earth, these environmental changes come slowly, allowing mutations and natural selection to change species in ways that work with the world around them. These changes in species occur faster when a smaller population is isolated, which allows advantageous mutations to remain and reoccur in subsequent generations. Evolutionary changes also come faster when the environment changes quickly, as happens when groups of a species migrate to new places. So what would happen to a small population of human colonists on Mars? Their environment is changed relatively suddenly. Gravity is different. Their life support system is nothing like that on Earth. Environmental radiation is greater. The very act of traveling to another planet may influence a human body in the original generation. So how would their offspring and a few more generations change? Read of some evolutionary possibilities for humans living on Mars at Astronomy. -via Real Clear Science As I was reading the article, allI could think of was "Dark They Were, and Golden-Eyed," the first Ray Bradbury story I ever read. It isn't about evolution as we know it, but humans who were sent to colonize Mars turned into Martians without having to reproduce, just because of the environment. #Mars #evolution #Martian
390 Million Years Ago, This Trilobite Developed a "Hyper-Eye" with 200 Lenses
Back in the 1970s, radiologist and amateur paleontologist Wilhelm Stürmer took some x-ray images of trilobites of the suborder Phacopina from the Devonian age. (These were arthropods that became extinct about 251 million years ago.) At the time, Stürmer believed that the filaments under the arthropod's eyes were nerves that served as a light guiding system. Unfortunately, scientists did not believe his theory. Now, decades later, a re-examination of Stürmer's images proved that his conjectures were true after all.The research team today has learned that the trilobite's eye system was unique. Each eye contained about 200 large lenses that spanned six normal compound-eye-facets, which formed a compound eye. Furthermore, scientists have identified a structure thought to directly process visual information from this hyper-eye.It is believed that this hyper-eye was an evolutionary adaptation, as the trilobite lived in low-light environments.Learn more about this trilobite and the study over at the University of Cologne.(Image via University of Cologne)#Evolution #Trilobite #Eye #XrayImageAnalysis #Adaptation
Is This the Most Successful Animal Ever?
To be honest, this question all depends on how you define a "successful animal." But trilobites had innovative features, branched out into many species, and lasted for many millions of years. While you may recognize a trilobite fossil, how much do you really know about these amazing creatures?
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