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Humankind’s common ancestor with other mammals may have been a roughly rat-size animal that weighed no more than a half a pound, had a long furry tail and lived on insects.

In a comprehensive six-year study of the mammalian family tree, scientists have identified and reconstructed what they say is the most likely common ancestor of the many species on the most abundant and diverse branch of that tree — the branch of creatures that nourish their young in utero through a placenta. The work appears to support the view that in the global extinctions some 66 million years ago, all non-avian dinosaurs had to die for mammals to flourish.

a combination of genetic and anatomical data established that the ancestor emerged within 200,000 to 400,000 years after the great dying at the end of the Cretaceous period. At the time, the meek were rapidly inheriting the earth from hulking predators like T. rex.

Natural disasters have triggered at least five mass extinctions in the past 500 million years, each of which wiped out between 50 and 90 percent of all species on the planet

it's happening again. A 2015 study reported the long-suspected sixth mass extinction of Earth's wildlife is "already underway." And a 2017 study calls the loss of that wildlife a “biological annihilation” and a “frightening assault on the foundations of human civilization.

And while previous extinctions were often linked to asteroids or volcanoes, this one is an inside job. It's caused mainly by one species — a mammal,

The now-prophetic words could be found at the end of a research paper published in the journal Clinical Microbiology Reviews in October of 2007: “The presence of a large reservoir of SARS-CoV-like viruses in horseshoe bats, together with the culture of eating exotic mammals in southern China, is a time bomb.”

The warning—made nearly 13 years ago and more than four years after the worrying first wave of severe acute respiratory syndrome, or SARS, killed nearly 800 people globally—was among the earliest to predict the emergence of something like SARS-CoV-2, the virus behind the current COVID-19 pandemic.

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the most striking feature of this early age of mammals is that it was almost unbelievably hot, so hot that around 50 million years ago there were crocodiles, palm trees, and sand tiger sharks in the Arctic Circle. On the other side of the blue-green orb, in waters that today would surround Antarctica, sea-surface temperatures might have topped an unthinkable 86 degrees Fahrenheit, with near-tropical forests on Antarctica itself. There were perhaps even sprawling, febrile dead zones spanning the tropics, too hot even for animal or plant life of any sort.

This is what you get in an ancient atmosphere with around 1,000 parts per million (ppm) of carbon dioxide. If this number sounds familiar, 1,000 ppm of CO2 is around what humanity is on pace to reach by the end of this century. That should be mildly concerning.

“You put more CO2 in the atmosphere and you get more warming, that’s just super-simple physics that we figured out in the 19th century,” says David Naafs, an organic geochemist at the University of Bristol. “But exactly how much it will warm by the end of the century, we don’t know. Based on our research of these ancient climates, though, it’s probably more than we thought.”

US wildlife authorities have launched an investigation after a manatee was discovered with the word 'Trump' scraped on its back.

The marine mammal was spotted on Sunday in Florida's Homosassa River, with the US president's surname on its body.

Officials told AP news agency that the animal does not appear to be seriously injured, and the word was scraped onto algae growing on its skin.

“The plague” conjures up images of the Black Death of Europe in the fourteenth century. This apocalyptic pestilence became known as the “black death” because infected people often developed buboes, swollen lymph nodes in the groin and neck, that turned black. Europe’s population was halved in four years. But that doesn’t cover the half of it. The pandemic also swept through Africa, the Middle East, and Asia. Some estimates of mortality go as high as two hundred million.

The third outbreak in China and India in the 1890s was the last major plague pandemic, claiming twelve million lives, mostly in India. The disease, which develops quickly and can kill within days, was fatal in the majority of cases.

Butler notes that the plague is still alive and well amongst certain wild mammals.

The human species Homo erectus evolved out of earlier human forms 1.8 million years ago and survived until 143,000 years ago. He and she walked on two feet and used tools and gradually spread over Africa and western and eastern Asia. Out of Homo erectus evolved, it is thought, Homo heidelbergensis. This common ancestor of both Homo neanderthalensis and Homo sapiens existed from 400,000 to 350,000 years ago. Homo heidelbergensis used fire and was the first to build shelters as opposed to just finding shelter, although they did that too. The European branch of Homo heidelbergensis evolved into the Neandertals 300,000 or more years ago. The Neandertals were big-bodied, light-skinned, cold-adapted humans. Some, at least, were redheads. The African branch of Homo heidelbergensis evolved into Homo sapiens—us—200,000 years ago. We were slighter-bodied. We had narrower hips and darker skin

Homo sapiens began moving out of Africa to the Near East 40,000 years ago. There they encountered a southern remnant of Neandertals. Most of that species had long since gone extinct. But we shared the region for 15,000 years, until the Neandertals disappeared.

Contrary to previous suppositions and speculations, Neandertals ate a varied diet including not only large mammals like mammoths but also birds, rabbits, and seafood. They possessed the “language gene,” just as we do, and likely communicated in some sort of language. They manufactured tools, although not in as great a variety as we did. They decorated their bodies and wore jewelry—an index of symbolic cognition. They likely adorned themselves with feathers.

When we've actually investigated monogamy in the animal kingdom, we've discovered that monogamy is close to non-existent. Almost no mammals mate for life

Even the reputedly monogamous world of birds - remember Nora Ephron's words "Want monogamy? Marry a swan!"? - what we thought we knew, we found out to be false:

Reports of extra-pair copulations -- henceforth, E.P.C.'s -- in animals previously thought to be monogamous have come hot and heavy during the last decade

Last month, the University of California system announced that a version of the Big History Project course could be counted in place of a more traditional World History class, paving the way for the state’s 1,300 high schools to offer it.

“We didn’t know when the last time was that somebody introduced a new course into high school,” Gates told me. “How does one go about it? What did the guy who liked biology — who did he call and say, ‘Hey, we should have biology in high school?’ It was pretty uncharted territory. But it was pretty cool.”

The American high school experience, at least as we now know it, is a relatively recent invention. Attendance did not start to become mandatory until the 1850s, and the notion of a nationwide standardized curriculum didn’t emerge until the turn of the century. But by the early 1900s, most children were taking the same list of classes that remains recognizable to this day: English, math, science and some form of history. For much of the 20th century, this last requirement would usually take the form of Western Civilization, a survey course that focused on European countries from around the rise of Rome through modernity.

we’ve left the Holocene behind — that’s the geological epoch since the end of the last ice age — and entered “a post-Holocene…geological age of our own making,” now best known as the Anthropocene.

the Anthropocene Working Group (because of my early writings, I’m a lay member), has moved substantially from asking whether such a transition has occurred to deciding when.

1950 as the starting point, indicated by a variety of markers, including the global spread of carbon isotopes from nuclear weapon detonations starting in 1945 and the mass production and disposal of plastics.

The recent excavation of a cave site along Portugal's coast revealed a wealth of fossilized remains of food, including fish, birds and mammals. It's estimated that Neanderthals lived in the cave, known as Figueira Brava, between 86,000 and 106,000 years ago.

From the sea, they could feast on limpet, mussels, clams, brown crabs, spider crabs, sharks, eels, sea breams, mullets, dolphins and seals. Marine birds also included mallards, common scoters (a large sea duck), geese, cormorants, gannets, shags, auks, egrets and loons.

Neanderthals living in Italy and across the Iberian Peninsula likely would have followed a similar lifestyle with a Mediterranean climate.

The scientists who study how diseases emerge in a changing environment knew this moment was coming. Climate change is making outbreaks of disease more common and more dangerous.

Over the past few decades, the number of emerging infectious diseases that spread to people — especially coronaviruses and other respiratory illnesses believed to have come from bats and birds — has skyrocketed.

A new emerging disease surfaces five times a year. One study estimates that more than 3,200 strains of coronaviruses already exist among bats, awaiting an opportunity to jump to people.

this North African resident became the latest victim of the ‘sixth great wave’ of mass extinction.

including the one that ended the dinosaurs’ reign 65 million years ago, and the one that we’re on the brink of today

scientists estimate that there’ll be between 269-350 further extinctions of birds and mammals by 2100.

The most popular reward for hiking to the top of Fu Shan, a hill near Hong Kong’s westernmost point, is a selfie backed by the setting sun, the gleaming new bridge across the Pearl River or a flight landing at the nearby airport.But for those who look more closely, there is the chance of a rarer prize: a glimpse of Chinese white dolphins swimming among fishing boats and cargo ships in the milky jade water.

The species, also known as the pink dolphin for the flush coloration it gets while swimming actively in warm waters, is found through much of coastal south China and Southeast Asia.

The marine mammals have maintained a precarious existence in the Pearl River Delta, which has the world’s second-highest volume of freight shipments, several cities with populations in the millions and an unrelenting pace of development in and along its waters.

Viewed zoologically, we humans are Homo sapiens, a culture-bearing upright-walking species that lives on the ground and very likely first evolved in Africa about 315,000 years ago.

the exact nature of our evolutionary relationships has been the subject of debate and investigation since the great British naturalist Charles Darwin published his monumental books On the Origin of Species (1859) and The Descent of Man (1871).

In fact, the human “family tree” may be better described as a “family bush,” within which it is impossible to connect a full chronological series of species, leading to Homo sapiens, that experts can agree upon.

Aristotle, Greek Aristoteles, (born 384 bce, Stagira, Chalcidice, Greece—died 322, Chalcis, Euboea), ancient Greek philosopher and scientist, one of the greatest intellectual figures of Western history.

He was the author of a philosophical and scientific system that became the framework and vehicle for both Christian Scholasticism and medieval Islamic philosophy.

Aristotle’s intellectual range was vast, covering most of the sciences and many of the arts,

Human destruction of the living world is causing a “frightening” number of plant extinctions, according to scientists who have completed the first global analysis of the issue.

“Plants underpin all life on Earth,” said Dr Eimear Nic Lughadha, at the Royal Botanic Gardens, Kew, who was part of the team. “They provide the oxygen we breathe and the food we eat, as well as making up the backbone of the world’s ecosystems – so plant extinction is bad news for all species.”

She said the true extinction rate for plants could easily be orders of magnitude

An analysis of clam shells and volcanic rocks from an Italian cave shows that Neanderthals collected shells and pumice from beaches. And due to specific indicators on some of the shells, the researchers also believe Neanderthals waded and dove into the ocean to retrieve shells, meaning they may have been able to swim.

It's fortunate that the shells, as well as the volcanic rock called pumice, were retrieved from the cave and stored at the Italian Institute of Human Paleontology because the cave itself is no longer accessible. Blasting for coastal highway construction buried the cave in the early 1970s.

Shell tools for Neanderthals are rare, and only a few examples of them have been discovered. The majority of tools associated with Neanderthals involve stone spear tips and stone hammers. But there was even less evidence prior to this study that Neanderthals living in Western Europe dove underwater. The study published Wednesday in the journal PLOS.

Some 66 million years ago, forests burned to the ground and the oceans acidified after the Chicxulub meteorite hit Earth in the Gulf of Mexico. Around the same time, on the other side of the planet, erupting volcanoes were busy covering much of the Indian subcontinent with lava, forming the Deccan Traps.

The meteorite, according to a team of scientists, was the chief perpetrator, while the volcanism, driving climate change in the background, might have affected life’s recovery in the wake of the impact.

The group found that global temperatures were much lower around the time of the extinction than they should have been if volcanoes were expelling large amounts of carbon dioxide. The volcanism, Dr. Hull explained, stopped seeping carbon dioxide into the atmosphere some 200,000 years before the Cretaceous ended and the age of mammals began. That means any harmful warming caused by carbon dioxide was already over by the time the meteorite hit.

Because of melting sea ice, it is likely that more polar bears will soon starve, warns a new study that discovered the large carnivores need to eat 60 percent more than anyone had realized.

Polar bears rely almost exclusively on a calorie-loaded diet of seals. To minimize their energy consumption the bears still-hunt, waiting for hours by seals’ cone-shaped breathing holes in the sea ice. When a seal surfaces to breathe the bear stands on its hind legs and smacks it on the head with both of its front paws to stun it. Then the bear bites it on the neck and drags it onto the ice.

Climate change is heating up the Arctic faster than anywhere else, and sea ice is shrinking 14 percent per decade. Even today, in the middle of the bitter cold Arctic winter, satellites show there is about 770,000 square miles less sea ice than the 1981 to 2010 median (That's an area larger than Alaska and California combined). In the late spring, the ice is breaking up sooner and forming later in the fall, forcing bears to burn huge amounts of energy walking or swimming long distances to get to any remaining ice. Or they stay on land longer, spending the summer and, increasingly, the fall fasting, living off their fat from the seals they caught in the spring.