How evolution works

Examples of phenotypic innovations across the eukaryotic tree of life, to which newly developed approaches can be applied.
Graphic Credit: Kenji Fukushima

What genetic changes are responsible for the evolution of phenotypic traits? This question is not always easy to answer. A newly developed method now makes the search much easier.

With its powerful digging shovels, the European mole can burrow through the soil with ease. The same applies to the Australian marsupial mole. Although the two animal species live far apart, they have developed similar organs in the course of evolution - in their case, extremities ideally adapted for digging in the soil.

Science speaks of "convergent evolution" in such cases, when animal, but also plant species independently develop features that have the same shape and function. There are many examples of this: Fish, for example, have fins, as do whales, although they are mammals. Birds and bats have wings, and when it comes to using poisonous substances to defend themselves against attackers, many creatures, from jellyfish to scorpions to insects, have all evolved the same instrument: the venomous sting.

Researchers Find that Wind Turbines Repel Bats in Finnish Forests

Northern bat (Eptesicus nilssonii) is the most common bat in Finland.
Photo Credit: Anna Blomberg

Wind turbines are built at an increasing pace but their effect on nature and animals is poorly known. Researchers from the Universities of Turku and Helsinki in Finland have investigated the impact of wind turbines on bat presence and activity in boreal forests. The results indicate clearly that bats don’t like wind turbines.

The researchers recorded bat acoustic activity for an entire summer at seven wind farms located in forests situated on the western coastline of Finland. By setting up recorders at varying distances from the wind turbines, they were able to see how bat activity and presence differed closer to the turbines as well as further away.

The researchers studied two groups of bats: the Northern bat, which is the most common species in Finland, and the Myotis, a group of five species, including the very common Daubenton’s bat.

“Our results showed that bat presence was impacted by the presence of wind turbines as both studied groups were found more often further away from the wind turbines. Northern bats were repelled up to 800 meters from the wind turbines, but for the Myotis species the negative impact of wind power was even greater than one kilometer, which was the maximum distance we studied”, summarizes lead author, Doctoral Researcher Simon Gaultier from the University of Turku.

A Theory of Rage

Left: Aditya Nair, Caltech graduate student and study's lead author. Photo Credit: J. Ehlert
Center: Ann Kennedy, Theoretical neuroscientist. Photo Credit: Ann Kennedy
Right: David Anderson, Professor of Biology Photo Credit: Courtesy of David Anderson

Have you ever been cut off while driving and found yourself swearing and laying on the horn? Or come home from a long day at work and lashed out at whoever left the dishes unwashed? From petty anger to the devastating violence we see in the news, acts of aggression can be difficult to comprehend. Research has yielded puzzling paradoxes about how rage works in the brain. But a new study from Caltech, pioneering a machine-learning research technique in the hypothalamus, reveals unexpected answers on the nature of aggression.

The hypothalamus is a brain region linked to many innate survival behaviors like mating, hunting, and the fight-or-flight response. Scientists have long believed that neurons in the hypothalamus are functionally specific—that is, certain groups of neurons correlate to certain specific behaviors. This seems to be the case in mating behavior, where neuron groups in the medial preoptic area (MPOA) of the hypothalamus, when stimulated, cause a male mouse to mount a female mouse. These same neurons are active when mounting behavior occurs naturally. The logical conclusion is that these neurons control mounting in mice.

Ludwig Cancer Research study uncovers novel aspect of tumor evolution and potential targets for therapy

 Ping-Chih Ho, Ludwig Lausanne Associate Member
Photo Credit: Ludwig Cancer Research

A Ludwig Cancer Research study has discovered that the immune system’s surveillance of cancer can itself induce metabolic adaptations in the cells of early-stage tumors that simultaneously promote their growth and equip them to suppress lethal immune responses.

Led by Ludwig Lausanne Associate Member Ping-Chih Ho and published in Cell Metabolism, the study details the precise mechanism by which this “immunometabolic editing” of emergent tumors occurs in mouse models of the skin cancer melanoma and identifies a novel biochemical signaling cascade and proteins that orchestrate its effects. Aside from illuminating a previously unknown dimension of tumor evolution, the findings hold significant promise for improving the efficacy of cancer immunotherapy.

“We have uncovered dozens of metabolic enzymes that contribute to immune evasion in melanoma tumors,” said Ho. “These enzymes, as well as some of the individual components of the signaling pathway we’ve identified, represent a rich trove of potential drug targets to undermine the defenses erected by immunometabolic editing. Such drugs could make tumors vulnerable to immune clearance and could also be used in combination with checkpoint blockade and other immunotherapies to overcome the resistance most cancers have to such treatments.”

New approach successfully traces genomic variants back to genetic disorders

Doctors researching DNA and genetics.
Illustration Credit: Julia Fekecs, NHGRI

National Institutes of Health researchers have published an assessment of 13 studies that took a genotype-first approach to patient care. This approach contrasts with the typical phenotype-first approach to clinical research, which starts with clinical findings. A genotype-first approach to patient care involves selecting patients with specific genomic variants and then studying their traits and symptoms; this finding uncovered new relationships between genes and clinical conditions, broadened the traits and symptoms associated with known disorders, and offered insights into newly described disorders. The study was published in the American Journal of Human Genetics.

“We demonstrated that genotype-first research can work, especially for identifying people with rare disorders who otherwise might not have been brought to clinical attention,” says Caralynn Wilczewski, Ph.D., a genetic counselor at the National Human Genome Research Institute’s (NHGRI) Reverse Phenotyping Core and first author of the paper.

Typically, to treat genetic conditions, researchers first identify patients who are experiencing symptoms, then they look for variants in the patients’ genomes that might explain those findings. However, this can lead to bias because the researchers are studying clinical findings based on their understanding of the disorder. The phenotype-first approach limits researchers from understanding the full spectrum of symptoms of the disorders and the associated genomic variants.

New quantum computing architecture could be used to connect large-scale devices

This image shows a module composed of superconducting qubits that can be used to directionally emit microwave photons.
Illustration Credit: Massachusetts Institute of Technology / Courtesy of the researchers

Quantum computers hold the promise of performing certain tasks that are intractable even on the world’s most powerful supercomputers. In the future, scientists anticipate using quantum computing to emulate materials systems, simulate quantum chemistry, and optimize hard tasks, with impacts potentially spanning finance to pharmaceuticals.

However, realizing this promise requires resilient and extensible hardware. One challenge in building a large-scale quantum computer is that researchers must find an effective way to interconnect quantum information nodes — smaller-scale processing nodes separated across a computer chip. Because quantum computers are fundamentally different from classical computers, conventional techniques used to communicate electronic information do not directly translate to quantum devices. However, one requirement is certain: Whether via a classical or a quantum interconnect, the carried information must be transmitted and received.

To this end, MIT researchers have developed a quantum computing architecture that will enable extensible, high-fidelity communication between superconducting quantum processors. In work published today in Nature Physics, MIT researchers demonstrate step one, the deterministic emission of single photons — information carriers — in a user-specified direction. Their method ensures quantum information flows in the correct direction more than 96 percent of the time.

James Webb Telescope Reveals Milky Way-like Galaxies in Young Universe

The power of JWST to map galaxies at high resolution and at longer infrared wavelengths than Hubble allows it look through dust and unveil the underlying structure and mass of distant galaxies. This can be seen in these two images of the galaxy EGS23205, seen as it was about 11 billion years ago. In the HST image (left, taken in the near-infrared filter), the galaxy is little more than a disk-shaped smudge obscured by dust and impacted by the glare of young stars, but in the corresponding JWST mid-infrared image (taken this past summer), it’s a beautiful spiral galaxy with a clear stellar bar.
Image Credit: NASA/CEERS/University of Texas at Austin

New images from NASA’s James Webb Space Telescope (JWST) reveal for the first-time galaxies with stellar bars — elongated features of stars stretching from the centers of galaxies into their outer disks — at a time when the universe was a mere 25% of its present age. The finding of so-called barred galaxies, similar to our Milky Way, this early in the universe will require astrophysicists to refine their theories of galaxy evolution.

Prior to JWST, images from the Hubble Space Telescope had never detected bars at such young epochs. In a Hubble image, one galaxy, EGS-23205, is little more than a disk-shaped smudge, but in the corresponding JWST image taken this past summer, it’s a beautiful spiral galaxy with a clear stellar bar.

“I took one look at these data, and I said, ‘We are dropping everything else!’” said Shardha Jogee, professor of astronomy at The University of Texas at Austin. “The bars hardly visible in Hubble data just popped out in the JWST image, showing the tremendous power of JWST to see the underlying structure in galaxies,” she said, describing data from the Cosmic Evolution Early Release Science Survey (CEERS), led by UT Austin professor, Steven Finkelstein.

New kind of scissors discovered

Professor Chase Beisel and Dr. Oleg Dmytrenko in the Würzburg HIRI laboratory.
Photo Credit: HIRI

Like a Swiss Army knife: a newly discovered component of bacterial immune defense paralyzes infected cells. He could advance molecular biological diagnostics.

Bacteria can also be infected by viruses, and they have developed their own immune defense strategies in this case. Bacterial defense systems such as CRISPR-Cas have various proteins and functions that help the bacteria protect themselves against intruders.

The defense is based on a common basic mechanism: a CRISPR ribonucleic acid (crRNA), which serves as a "lead RNA", helps to identify regions of a foreign genome, such as the DNA of a virus, in order to make them specifically harmless. The nuclease led by a crRNA can cut its target like scissors. It is a strategy of nature that humans have made use of technologically in a variety of ways.

"When you consider how well different nucleases have been implemented in new and improved technologies, any discovery in this area could bring new benefits to society," Professor Chase Beisel describes a research motivation of his laboratory at the Helmholtz Institute for RNA-based in Würzburg Infection research (HIRI). The facility is a location of the Helmholtz Center for Infection Research in Braunschweig in cooperation with the Julius Maximilians University, to which Chase Beisel is the head of the chair for synthetic RNA biology.

Climate change could cause “disaster” in the world’s oceans

J. Keith Moore, UCI professor of Earth system science, says, “… unchecked global warming could lead to a shutdown of the ocean deep circulation. This would be a climate disaster similar in magnitude to complete melting of the ice sheets on land.”
Photo Credit: Steve Zylius / UCI

Climate-driven heating of seawater is causing a slowdown of deep circulation patterns in the Atlantic and Southern oceans, according to University of California, Irvine Earth system scientists, and if this process continues, the ocean’s ability to remove carbon dioxide from the atmosphere will be severely limited, further exacerbating global warming.

In a recent study published in Nature Climate Change, these researchers analyzed projections from three dozen climate models and found that the Atlantic Meridional Overturning Circulation and the Southern Meridional Overturning Circulation will slow by as much as 42 percent by 2100. The simulations suggest that under worst-case warming, the SMOC could cease entirely by 2300.

“Analysis of the projections from 36 Earth system models over a range of climate scenarios shows that unchecked global warming could lead to a shutdown of the ocean deep circulation,” said co-author J. Keith Moore, UCI professor of Earth system science. “This would be a climate disaster similar in magnitude to complete melting of the ice sheets on land.”

Antibiotic residues in water a threat to human health

Photo Credit: Thomas Hoang

Antibiotic residues in wastewater and wastewater treatment plants in regions around China and India risk contributing to antibiotic resistance, and the drinking water may pose a threat to human health, according to an analysis from Karolinska Institutet published in The Lancet Planetary Health. The researchers also determined the relative contribution of various sources of antibiotic contamination in waterways, such as hospitals, municipals, livestock, and pharmaceutical manufacturing.

” Our results can help decision-makers to target risk reduction measures against environmental residues of priority antibiotics and in high-risk sites, to protect human health and the environment,” says Nada Hanna, researcher at the Department of Global Public Health at Karolinska Institutet, and the study’s first author. “Allocating these resources efficiently is especially vital for resource-poor countries that produce large amounts of antibiotics.”

Bacteria that become resistant to antibiotics are a global threat that can lead to untreatable bacterial infections in animals and humans.

Antibiotics can enter the environment during their production, consumption and disposal. Antibiotic residues in the environment, such as in wastewater and drinking water, can contribute to the emergence and spread of resistance.