ScienceDaily: Top Environment News

PCB contamination in Icelandic orcas: a matter of diet

Posted: 06 May 2021 02:41 PM PDT

A new study suggests that some Icelandic killer whales have very high concentrations of PCBs (polychlorinated biphenyls) in their blubber. But it seems that other orcas from the same population have levels of PCBs that are much lower. It mainly depends on what they eat.

Swiping, swabbing elevates processing plant food safety

Posted: 06 May 2021 02:41 PM PDT

By swiping surfaces in commercial food processing plants with specially designed rapid-testing adenosine triphospate (ATP) swabs -- which produce a light similar to the glow of fireflies in the presence of microorganisms -- spoilage and foodborne illness could diminish, according to a new study.

Scrap for cash before coins

Posted: 06 May 2021 02:41 PM PDT

How did people living in the Bronze Age manage their finances before money became widespread? Researchers ave discovered that bronze scrap found in hoards in Europe circulated as a currency. These pieces of scrap -- which might include swords, axes, and jewellery broken into pieces -- were used as cash in the late Bronze Age, and in fact complied with a weight system used across Europe.

Most human origins stories are not compatible with known fossils

Posted: 06 May 2021 11:21 AM PDT

In the 150 years since Charles Darwin speculated that humans originated in Africa, the number of species in the human family tree has exploded, but so has the level of dispute concerning early human evolution. A new review looks at the major discoveries in hominin origins since Darwin's works and argues that fossil apes can inform us about essential aspects of ape and human evolution, including the nature of our last common ancestor.

The cerebellum may have played an important role in the evolution of the human brain

Posted: 06 May 2021 11:20 AM PDT

The cerebellum -- a part of the brain once recognized mainly for its role in coordinating movement -- underwent evolutionary changes that may have contributed to human culture, language and tool use, according to a new study.

Sharks use Earth's magnetic fields to guide them like a map

Posted: 06 May 2021 11:20 AM PDT

Sea turtles are known for relying on magnetic signatures to find their way across thousands of miles to the very beaches where they hatched. Now, researchers have some of the first solid evidence that sharks also rely on magnetic fields for their long-distance forays across the sea.

Artificial color-changing material that mimics chameleon skin can detect seafood freshness

Posted: 06 May 2021 11:20 AM PDT

Scientists have designed an artificial color-changing material that mimics chameleon skin, with luminogens (molecules that make crystals glow) organized into different core and shell hydrogel layers instead of one uniform matrix. The findings demonstrate that a two-luminogen hydrogel chemosensor developed with this design can detect seafood freshness by changing color in response to amine vapors released by microbes as fish spoils.

Blocking viruses' exit strategy

Posted: 06 May 2021 09:57 AM PDT

Tests of a new antiviral that aims to prevent the deadly Marburg virus from spreading in the body show promise, according to a new study.

New study tracked large sharks during hurricanes

Posted: 06 May 2021 07:55 AM PDT

Biologists tracked large sharks in Miami and The Bahamas to understand how these migratory animals respond to major storms, like hurricanes.

Many consumers misinterpret food date labels, yet use them with confidence

Posted: 06 May 2021 07:54 AM PDT

Misunderstanding food date labeling is common and educational communications are needed to improve consumer understanding, according to a new study.

First member of ill-fated 1845 Franklin expedition is identified by DNA analysis

Posted: 06 May 2021 07:54 AM PDT

The identity of the skeletal remains of a member of the 1845 Franklin expedition has been confirmed using DNA and genealogical analyses by a team of researchers.

Alzheimer's study: A Mediterranean diet might protect against memory loss and dementia

Posted: 06 May 2021 07:53 AM PDT

Alzheimer's disease is caused by protein deposits in the brain and the rapid loss of brain matter. But a Mediterranean diet rich in fish, vegetables and olive oil might protect the brain from these disease triggers.

Earliest evidence of humans changing ecosystems with fire

Posted: 05 May 2021 11:55 AM PDT

A new study provides the earliest evidence to date of ancient humans significantly altering entire ecosystems with flames. The study combines archaeological evidence -- dense clusters of stone artifacts dating as far back as 92,000 years ago -- with paleoenvironmental data on the northern shores of Lake Malawi in eastern Africa to document that early humans were ecosystem engineers.

New ant species named in recognition of gender diversity

Posted: 05 May 2021 10:05 AM PDT

A rare and unusual newly discovered ant from Ecuador has been named Strumigenys ayersthey, with the suffix '-they' chosen in contrast to traditional naming practices which, to date, fail to recognize gender diversity formally. The new species is distinguished by its predominantly smooth and shining cuticle surface and long trap-jaw mandibles.

Meet the freaky fanged frog from the Philippines

Posted: 05 May 2021 08:13 AM PDT

Biologists have described a new species of fanged frog discovered in the Philippines known as the Mindoro Fanged Frog.

How mitochondria make the cut

Posted: 05 May 2021 08:13 AM PDT

With the help of their custom-built super-resolution microscope, biophysicists have discovered where and why mitochondria divide, putting to rest controversy about the underlying molecular machinery of mitochondrial fission. Mitochondria either split in half or cut off their ends to self-regulate.

Bees thrive where it's hot and dry: A unique biodiversity hotspot located in North America

Posted: 05 May 2021 08:13 AM PDT

Rarely has the United States-Mexico border become the source of positive news of lately. However, a new study demonstrates it's one of the world's top biodiversity hotspots for bees. A multi-year survey found more than 470 bee species in 16km2 of Chihuahuan Desert, equivalent to 14% of all known bee species from the United States.

3D bioprinting technique controls cell orientation

Posted: 05 May 2021 08:13 AM PDT

Scientists have developed a new approach for directing cell orientation within deposited hydrogel fibers via a method called multicompartmental bioprinting.

Tracking down the tiniest of forces: How T cells detect invaders

Posted: 05 May 2021 07:20 AM PDT

What happens on a molecular level, when our immune system detects antigens? Scientists have found out, how T cells exert tiny forces on antigens. Bonds between T cells and antigen presenting cells break, and this behavior tells the T cell whether or not it has found the right antigen.

Ancient DNA reveals origin of first Bronze Age civilizations in Europe

Posted: 05 May 2021 07:20 AM PDT

The first civilisations to build monumental palaces and urban centres in Europe are more genetically homogenous than expected, according to genomes gathered from archaeological sites around the Aegean. Individuals from the northern Aegean were considerably different by the Middle Bronze Age, sharing half their ancestry with people from the Pontic-Caspian steppe. These populations were highly similar to present-day Greeks. This supports theories that Proto-Greek and Indo-European languages originated in Anatolia or the Pontic-Caspian Steppe region.

Bats know the speed of sound from birth, scientists discovery

Posted: 05 May 2021 07:20 AM PDT

Unlike humans, who map the world in units of distance, bats map the world in units of time. What this means is that the bat perceives an insect as being at a distance of nine milliseconds, and not one and a half meters, as was previously thought.

Legendary Sargasso Sea may be sea turtles' destination during mysterious 'lost years'

Posted: 05 May 2021 06:44 AM PDT

New research indicates that the legendary Sargasso Sea, which includes part of the Bermuda Triangle and has long featured in fiction as a place where ships go derelict, may actually be an important nursery habitat for young sea turtles. Researchers presented evidence of baby green sea turtles arriving at the Sargasso Sea after entering the ocean off the east coast of Florida.

Cryptic sense of orientation of bats localized: the sixth sense of mammals lies in the eye

Posted: 05 May 2021 04:50 AM PDT

Mammals see with their eyes, hear with their ears and smell with their nose. But which sense or organ allows them to orient themselves on their migrations, which sometimes go far beyond their local foraging areas and therefore require an extended ability to navigate? Scientific experiments now show that the cornea of the eyes is the location of such an important sense in migrating bats.

A trait of the rare few whose bodies naturally control HIV: 'trained' immune cells

Posted: 04 May 2021 04:15 PM PDT

Scientists have discover that 'elite controllers' have myeloid dendritic cells that display characteristics of trained innate immune cells.

Team cracks century-old mystery over the health struggles of explorer Ernest Shackleton

Posted: 04 May 2021 08:26 AM PDT

Over the years, physicians and historians have attributed Shackleton's failing health during his Antarctic expeditions to scurvy or a congenital heart defect. By studying other explorers and learning they had symptoms comparable to those of Shackleton, researchers concluded that beriberi provided a sound scientific and medical explanation for the famed explorer's health struggles.