Fossils in the ‘Cradle of Humankind’ may be more than a million years older than previously thought

Darryl Granger of Purdue University developed the technology that updated the age of an Australopithecus found in Sterkfontein Cave. New data pushes its age back more than a million years, to 3.67 million years old.
Purdue University photo/Lena Kovalenko

The earth doesn’t give up its secrets easily – not even in the “Cradle of Humankind” in South Africa, where a wealth of fossils relating to human evolution have been found.

For decades, scientists have studied these fossils of early human ancestors and their long-lost relatives. Now, a dating method developed by a Purdue University geologist just pushed the age of some of these fossils found at the site of Sterkfontein Caves back more than a million years. This would make them older than Dinkinesh, also called Lucy, the world’s most famous Australopithecus fossil.

The “Cradle of Humankind” is a UNESCO World Heritage Site in South Africa that comprises a variety of fossil-bearing cave deposits, including at Sterkfontein Caves. Sterkfontein was made famous by the discovery of the first adult Australopithecus, an ancient hominin, in 1936. Hominins includes humans and our ancestral relatives, but not the other great apes. Since then, hundreds of Australopithecus fossils have been found there, including the well-known Mrs. Ples, and the nearly complete skeleton known as Little Foot. Paleoanthropologists and other scientists have studied Sterkfontein and other cave sites in the Cradle of Humankind for decades to shed light on human and environmental evolution over the past 4 million years.

Darryl Granger, a professor of earth, atmospheric, and planetary sciences in Purdue University’s College of Science, is one of those scientists, working as part of an international team. Granger specializes in dating geologic deposits, including those in caves. As a doctoral student, he devised a method for dating buried cave sediments that is now used by researchers all over the world. His previous work at Sterkfontein dated the Little Foot skeleton to about 3.7 million years old, but scientists are still debating the age of other fossils at the site.

New optical device could help solar arrays focus light, even under clouds

Different stages of the graded index glass pyramid fabrication: when in optical contact with a solar cell, the pyramid at the final step (bottom right corner) absorbs and concentrates most of the incident light and appears dark.
Image credit: Nina Vaidya

Stanford engineers’ optical concentrator could help solar arrays capture more light even on a cloudy day without tracking the sun

Researchers imagined, designed, and tested an elegant lens device that can efficiently gather light from all angles and concentrate it at a fixed output position. These graded index optics also have applications in areas such as light management in solid-state lighting, laser couplers, and display technology to improve coupling and resolution.

Even with the impressive and continuous advances in solar technologies, the question remains: How can we efficiently collect energy from sunlight coming from varying angles from sunrise to sunset?

Solar panels work best when sunlight hits them directly. To capture as much energy as possible, many solar arrays actively rotate towards the sun as it moves across the sky. This makes them more efficient, but also more expensive and complicated to build and maintain than a stationary system.

Light during sleep in older adults linked to obesity, diabetes, high blood pressure

In a sample of older men and women ages 63 to 84, those who were exposed to any amount of light while sleeping at night were significantly more likely to be obese, and have high blood pressure and diabetes compared to adults who were not exposed to any light during the night, reports a new Northwestern Medicine study.

Light exposure was measured with a wrist-worn device and tracked over seven days.

This is a real world (not experimental) study demonstrating the prevalence of any light exposure at night being linked to higher obesity, high blood pressure (known as hypertension) and diabetes among older adults.

“Whether it be from one’s smartphone, leaving a TV on overnight or light pollution in a big city, we live among an abundant number of artificial sources of light that are available 24 hours of a day,” said study corresponding author Dr. Minjee Kim, assistant professor of neurology at Northwestern University Feinberg School of Medicine and a Northwestern Medicine physician. “Older adults already are at higher risk for diabetes and cardiovascular disease, so we wanted to see if there was a difference in frequencies of these diseases related to light exposure at night.”

Study researchers were surprised to find that less than half of the 552 study participants consistently had a five-hour period of complete darkness per day. The rest of participants were exposed to some light even during their darkest five-hour periods of the day, which were usually in the middle of their sleep at night.

Oil and Gas Activity Linked to Most Recent Earthquakes in West Texas

The Yates Oil Field in the Delaware Basin.
Credit: Jan Buchholtz.

Since 2009, earthquakes have been rapidly rising in the Delaware Basin – a prolific oil-producing region in West Texas and New Mexico. According to a study led by researchers at The University of Texas at Austin, the majority of them can be linked to oil and gas production.

The researchers looked back on data that tracked seismicity and oil and gas production in the region from 2017 to 2020 and found that 68% of earthquakes above magnitude 1.5 were highly associated with one or more of the following oil and gas production activities: hydraulic fracturing or the disposal of produced formation water into either shallow or deep geologic formations. Formation water is found in all subsurface reservoirs and produced with oil and gas. Companies dispose of produced water by injecting it into geologic formations that are separate from oil and gas reservoirs.

All of these production activities are known to increase subsurface pore pressure, which is a mechanism for triggering earthquakes, said the study’s co-author, Alexandros Savvaidis, a researcher at the UT Bureau of Economic Geology and the principal investigator of Texas’ state seismic monitoring network and seismicity research TexNet, which is overseen by the bureau. By using a combination of statistical analysis and physics-based modeling, the study was able to disentangle which activities have a connection to past earthquakes.

“This paper shows that we now know a lot about how oil and gas activities and seismic activity are connected,” Savvaidis said. “The modeling techniques could help oil and gas producers and regulators identify potential risks and adjust production and disposal activity to decrease them.”

The study was published in Seismological Research Letters.

Southern resident killer whales not getting enough to eat since 2018

A southern resident killer whale.
Credit: NOAA, Ocean Wise

The endangered southern resident killer whale population isn’t getting enough to eat, and hasn’t been since 2018, a new UBC study has determined.

The animals have been in an energy deficit, averaging across spring, summer and fall, for six of the last 40 years—meaning the energy they get from food is less than what they expend. Three of those six years came in the most recent years of the study, 2018 to 2020. The average difference in energy is 28,716 calories, or about 17 per cent of the daily required energy for an average adult killer whale, the authors say.

“With the southern resident population at such a low level, there’s a sense of urgency to this kind of research,” says lead author Fanny Couture, a doctoral student at the Institute for the Oceans and Fisheries (IOF) and Ocean Wise. “Both killer whales and Chinook salmon, the southern resident’s main prey, are important, iconic species for the west coast of Canada. Studying what is happening to the population may help offer solutions, both for the southern residents and potentially other killer whale populations in the future.”

The southern resident population, which feeds mainly on Chinook salmon, numbered 73 individuals as of October 2021, compared with the increasing northern resident population of about 300. Studies have posited that the growth of the southern resident population may be impeded by a lack of food.

Supernumerary virtual robotic arms can feel like part of our body

VR supernumerary robotic system. In this diagram of the system, the dotted lines represent wireless connections and solid lines represent wired connections.
Credit: 2022 Ken Arai.

Research teams at the University of Tokyo, Keio University and Toyohashi University of Technology in Japan have developed a virtual robotic limb system which can be operated by users’ feet in a virtual environment as extra, or supernumerary, limbs. After training, users reported feeling like the virtual robotic arms had become part of their own body. This study focused on the perceptual changes of the participants, understanding of which can contribute to designing real physical robotic supernumerary limb systems that people can use naturally and freely just like our own bodies.

What would you do with an extra arm, or if like Spider-Man’s nemesis Doctor Octopus, you could have an extra four? Research into extra, or supernumerary, robotic limbs look at how we might adapt, mentally and physically, to having additional limbs added to our bodies.

Doctoral student Ken Arai from the Research Center for Advanced Science and Technology (RCAST) at the University of Tokyo became interested in this research as a way to explore the limits of human “plasticity” — in other words, our brain’s ability to alter and adapt to external and internal changes. One example of plasticity is the way that we can learn to use new tools and sometimes even come to see them as extensions of ourselves, referred to as “tool embodiment,” whether it’s an artist’s paintbrush or hairdresser’s scissors.

Virus Discovery Offers Clues About Origins of Complex Life

Comparison of all known virus genomes. Those viruses with similar genomes are grouped together including those that infect bacteria (on the left), eukaryotes (on the right and bottom center). The viruses that infect Asgard archaea are unique from those that have been described before.
Credit: University of Texas at Austin.

The first discovery of viruses infecting a group of microbes that may include the ancestors of all complex life has been found, researchers at The University of Texas at Austin report in Nature Microbiology. The discovery offers tantalizing clues about the origins of complex life and suggests new directions for exploring the hypothesis that viruses were essential to the evolution of humans and other complex life forms.

There is a well-supported hypothesis that all complex life forms such as humans, starfish and trees — which feature cells with a nucleus and are called eukaryotes — originated when archaea and bacteria merged to form a hybrid organism. Recent research suggests the first eukaryotes are direct descendants of the so-called Asgard archaea. The latest research, by Ian Rambo (a former doctoral student at UT Austin) and other members of Brett Baker’s lab, sheds light on how viruses, too, might have played a role in this billions-year-old history.

“This study is opening a door to better resolving the origin of eukaryotes and understanding the role of viruses in the ecology and evolution of Asgard archaea,” Rambo said. “There is a hypothesis that viruses may have contributed to the emergence of complex cellular life.”

Researchers find deadly fungus can multiply by having sex, which could produce more drug-resistant, virulent strains

 Jianping Xu, professor in McMaster University’s
Department of Biology and researcher with Canada’s
Global Nexus for Pandemics and Biological Threats
Credit: McMaster University

Researchers at McMaster University have unlocked an evolutionary mystery of a deadly pathogen responsible for fueling the superbug crisis: it can reproduce by having sex.

And while such fraternizing is infrequent, scientists report it could be producing more drug-resistant and more virulent strains of Candida auris, capable of spreading faster.

C. auris is a fungus that can cause severe infections and sometimes death, often striking immunocompromised hospital patients.

Unlike animals and plants, microorganisms of this nature usually divide and reproduce asexually, so one produces two, two produce four and so on, all genetically identical to each other, through a process of very simple division and without the exchange of genetic material.

“One of the really complex and puzzling questions about this fungal pathogen is its origin and how it reproduces in nature,” says Jianping Xu, a professor in McMaster’s Department of Biology and researcher with Canada’s Global Nexus for Pandemics and Biological Threats.

For the study, recently published online in Computation and Structural Biotechnology Journal, researchers analyzed nearly 1,300 strains available on a public database of C. auris genome sequences. They searched for and confirmed recombination events, or sexual activity.

The findings will help to further research because scientists can now replicate those sexual behaviors in the lab.

“The research tells us that this fungus has been recombined in the past and can recombine in nature, which enables it to generate new genetic variants rather quickly,” explains Xu. “That may sound frightening, but it’s a double-edged sword. Because we learned they could recombine in nature, we could possibly replicate the process in the lab, which could allow us to understand the genetic controls of virulence and drug resistance and potentially other traits that make it such a dangerous pathogen, much faster.”

Long-term liquid water also on non-Earth-like planets?

Low-mass planets with a primordial atmosphere of hydrogen and helium might have the temperatures and pressures that allow water in the liquid phase. The presence of liquid water is favorable for life, so that these planets potentially harbor exotic habitats for billions of years.
Credit: (CC BY-NC-SA 4.0) - Thibaut Roger - Universität Bern - Universität Zürich

Liquid water is an important prerequisite for life to develop on a planet. As researchers from the University of Bern, the University of Zurich and the National Centre of Competence in Research (NCCR) PlanetS report in a new study, liquid water could also exist for billions of years on planets that are very different from Earth. This calls our currently Earth-centered idea of potentially habitable planets into question.

Life on Earth began in the oceans. In the search for life on other planets, the potential for liquid water is therefore a key ingredient. To find it, scientists have traditionally looked for planets similar to our own. Yet, long-term liquid water does not necessarily have to occur under similar circumstances as on Earth. Researchers of the University of Bern and the University of Zurich, who are members of the National Centre of Competence in Research (NCCR) PlanetS, report in a study published in the journal Nature Astronomy, that favorable conditions might even occur for billions of years on planets that barely resemble our home planet at all.

Will renaming carp help control them?

Joseph Parkos directs the Illinois Natural History Survey’s Kaskaskia, Ridge Lake and Sam Parr biological stations in Illinois.
Photo Credit: B. Gallo-Parkos

Illinois officials this month announced that Asian carp would now be called “copi” in an attempt to make the fish more desirable for eating. Joseph Parkos, the director of the Illinois Natural History Survey’s Kaskaskia, Ridge Lake and Sam Parr biological stations in Illinois, spoke with News Bureau life sciences editor Diana Yates about scientific initiatives to study and control carp/copi fish populations and the potential for rebranding to aid those efforts.

What are Asian carp/copi and where in Illinois are their populations a problem?

Silver carp produce more offspring than other carp species. 
Photo Credit: USGS