Human Evolution Led to an Extreme Thirst for Water

Asher Y. Rosinger

Scientific American | July 01, 2021

Human Evolution Led to an Extreme Thirst for Water
Credit: I AM A PHOTOGRAPHER AND AN ARTIST Getty Images

We trekked through the Bolivian Amazon, drenched in sweat. Draped head to toe in bug repellent gear, we stayed just ahead of the clouds of mosquitoes as we sidestepped roots, vines and giant ants. My local research assistant Dino Nate, my partner Kelly Rosinger and I were following Julio, one of my Tsimane’ friends and our guide on this day. Tsimane’ are a group of forager-horticulturalists who live in this hot, humid region. Just behind us, Julio’s three-year-old son floated happily through the jungle, unfazed by the heat and insects despite his lack of protective clothing, putting my perspiration-soaked efforts to shame.

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SCIENCE OF LIFE

The Secret Forces that Squeeze and Pull Life into Shape

Amber Dance

Nature | January 13, 2021

Microscopic image of a zebrafish embryo 22 hours postfertilization
Developing embryos, such as this zebrafish, rely on physical forces to sculpt them as they grow. Credit: Philipp Keller/HHMI Janelia Research Campus

At first, an embryo has no front or back, head or tail. It’s a simple sphere of cells. But soon enough, the smooth clump begins to change. Fluid pools in the middle of the sphere. Cells flow like honey to take up their positions in the future body. Sheets of cells fold origami-style, building a heart, a gut, a brain.Read More »

COVID-19 PANDEMIC

New research suggests immunity to COVID is better than we first thought

Nigel McMillan

The Conversation | November 26, 2020

Illustration of a B cellIllustration of an antibody-producing B cell. New research suggests our immune system can remember how to produce antibodies against SARS-CoV-2 at least eight months after infection, and probably even longer. Shutterstock

Early in the pandemic, many researchers feared people who contracted COVID could be reinfected very quickly. This was because several early studies showed antibodies seemed to wane after the first few months post-infection.

It was also partly because normal human coronaviruses, which are one cause of common colds and are cousins of SARS-CoV-2, do not generate long-lasting immunity, so we can get reinfected with them after 12 months.

But new preliminary research suggests key parts of the immune system can remember SARS-CoV-2 for at least eight or nine months, and possibly for years.Read More »

BIOLOGICAL SCIENCE 

Studying Life at the Extremes

Amber Dance

Nature | November 02, 2020

View over a larger crater with patches of burning fire and a figure in a silver suit and helmet suspended on a zip line overhead

Researchers are looking for microbes in soil samples from this flaming gas crater in Turkmenistan, known as the Door to Hell. Credit: Stefan Green/XMP

Microbes cling to life in some of Earth’s most extreme environments, from toxic hot springs to high-altitude deserts. These ‘extremophiles’ include organisms that can survive near-boiling heat or near-freezing cold, high pressure or high salt, as well as environments steeped in acids, alkalis, metals or radioactivity.Read More »

BIOLOGICAL SCIENCE 

These Bizarre Ancient Species are Rewriting Animal Evolution

Traci Watson

Nature | October 28, 2020

Artistic reconstruction of Fractofusus on the H14 surface, Bonavista Peninsula

Organisms named Fractofusus cover the sea floor some 560 million years ago, in a reconstruction of fossils from Newfoundland, Canada. Credit: Dr Charlotte G. Kenchington

The revolutionary animal lived and died in the muck. In its final hours, it inched across the sea floor, leaving a track like a tyre print, and finally went still. Then geology set to work. Over the next half a billion years, sediment turned to stone, preserving the deathbed scene. The fossilized creature looks like a piece of frayed rope measuring just a few centimetres wide. But it was a trailblazer among living things.

This was the earliest-known animal to show unequivocal evidence of two momentous innovations packaged together: the ability to roam the ocean floor, and a body built from segments. It was also among the oldest known to have clear front and back ends, and a left side that mirrored its right. Those same features are found today in animals from flies to flying foxes, from lobsters to lions.Read More »

BIOLOGICAL SCIENCE 

Ancient Dog DNA Reveals 11,000 Years of Canine Evolution

Ewen Callaway

Nature | October 29, 2020

Papua-New-Guinea singing dog captive, Papua-New-Guinea.
New Guinea singing dogs are related to Australian dingoes.Credit: Daniel Heuclin/NPL

Human history is for the dogs. The largest-ever study of ancient genomes from the animals suggests that where people went, so did their four-legged friends — to a point. The research also identified major regional shifts in human ancestry that left little mark on dog populations, as well as times when dogs changed, but their masters didn’t.

The analysis of more than two dozen Eurasian dogs also suggests the animals were domesticated and became widespread around the world well before 11,000 years ago. But it does not make any claims as to when or where domestication from wolves happened, an issue that has vexed researchers and sparked sometimes heated debate.Read More »

BIOLOGICAL SCIENCE

 

Scientists pull living microbes, possibly 100 million years old, from beneath the sea

Elizabeth Pennisi

Science | July 28, 2020

Researchers take samples from deep-ocean sediment cores. IODP JRSO

 

Microbes buried beneath the sea floor for more than 100 million years are still alive, a new study reveals. When brought back to the lab and fed, they started to multiply. The microbes are oxygen-loving species that somehow exist on what little of the gas diffuses from the ocean surface deep into the seabed.

The discovery raises the “insane” possibility, as one of the scientists put it, that the microbes have been sitting in the sediment dormant, or at least slowly growing without dividing, for eons.

The new work demonstrates “microbial life is very persistent, and often finds a way to survive,” says Virginia Edgcomb, a microbial ecologist at the Woods Hole Oceanographic Institution who was not involved in the work.

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Microbes are Striking Back

by Amit Sengupta

People’s DemocracyJuly 29, 2018

THE development of new knowledge is a fascinating exercise. Since humans evolved, they have been driven by curiosity to learn more and more about nature. Over time the knowledge accumulated came to be systematised and this is what we call science. The hunger for knowledge deepened and expanded our collective understanding of nature. This knowledge is utilised to create tools and other artifacts that humans use to improve conditions of living. Science has always been a collective activity, though under capitalism today there are attempts by corporations to claim ownerships over knowledge through the exercise of intellectual property rights – in the form of patents, copyrights, etc.Read More »