brain

Elephants have names

July 11, 2024 By EarthWise Leave a Comment

Elephants are considered to be very smart creatures. They have the largest brain of any land animal and have three times as many neurons as humans. Of course, a lot of that brain hardware is needed to control those big elephant bodies, but elephants have also demonstrated impressive mental capabilities on many occasions.

A new study by an international team headed by researchers from Colorado State University has found that elephants call each other by name and respond when they hear others call their name.

The researchers analyzed hundreds of elephant calls recorded over more than a year in Kenya. With machine learning techniques, they were able to identify specific sounds that elephants made when calling each other. When the researchers played recordings of these sounds, the elephants responded to the sound of their own name by calling back or moving toward the loudspeaker. Their response to other names was much less enthusiastic.

Very few animals use names at all, and, in most cases, it is more a matter of imitation. For example, dolphins refer to other dolphins by mimicking their unique sounds.

These findings at least suggest that elephants may be capable of abstract thought and perhaps may have a vocabulary beyond names for each other. The researchers are investigating whether elephants can identify food, water, or locations using their calls. The great hope is that it might ultimately be possible to communicate with elephants directly. It would be wonderful to be able to alert them to poachers or other threats. The lead author of the study said that he would like to be able to tell elephants things like “Do not come here. You’re going to be killed if you come here.”

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Elephants Have Names for Each Other, Study Finds

Photo, posted April 24, 2016, courtesy of Neil Ransom via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Pollution From Tires | Earth Wise

October 16, 2023 By EarthWise Leave a Comment

A few years ago, researchers investigating massive deaths of coho salmon in West Coast streams discovered that the water contained particles from vehicle tires. The cause of the fish mortality turned out to be a chemical called 6PPD that is added to tires to prevent cracking and degradation. The mystery was solved, but so far, the chemical continues to be used by all major tire manufacturers and is found on roads and in waterways around the world.

Worse still, the acute toxicity of 6PPD and the chemicals that it transforms into when exposed to ground-level ozone is only the tip of the tire pollution iceberg. Tire rubber contains more than 400 chemicals and compounds, many of which are carcinogenic.

About 2 billion tires are sold across the globe each year and that number is expected to reach 3.4 billion by 2030. Tires are made from about 20% natural rubber and 24% synthetic rubber, which requires about 4 gallons of petroleum per tire. Hundreds of other ingredients – including steel, fillers, heavy metals like copper, cadmium, lead, and zinc – make up the rest.

Tire wear particles are emitted continually as vehicles travel. They range in size from visible pieces of rubber or plastic to microparticles. Research has shown that a car’s four tires collectively emit half a trillion ultrafine particles per mile driven. These particles are small enough to be breathed into the lungs and can travel throughout the body and even cross the blood-brain barrier. Particle pollution from tires exceeds that from tailpipes.

Tire pollution is a huge problem that is just starting to receive the attention it deserves.

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Road Hazard: Evidence Mounts on Toxic Pollution from Tires

Photo, posted June 22, 2018, courtesy of Tony Webster via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Computing With Honey | Earth Wise

April 28, 2022 By EarthWise Leave a Comment

Researchers are always working to develop faster and more powerful computers. Some of them believe that the future of computing lies with neuromorphic computers, which are systems designed to mimic the neurons and synapses found in the human brain.

The human brain has more than 100 billion neurons with more than 1 quadrillion synapses or connections among them. These numbers far exceed anything people have built. There have been some neuromorphic computer chips made that have the equivalent of more than 100 million neurons per chip, but this is still far less than the number in the brain. Despite all its complexity, the brain uses vastly less power than a powerful computer. Some supercomputers use tens of millions of watts to operate; the brain uses around 10 to 20 watts.

Many researchers are searching for biodegradable and renewable ways to make neuromorphic computing components. Researchers at Washington State University have demonstrated a way to make them using, of all things, honey. The honey is used to form a memristor, which is a component similar to a transistor that can both process and store data in memory. The device uses honey processed into a solid form and sandwiched between two metal electrodes. The organic device is very stable and reliable over a long time.

So far, these devices are on a micro scale – about the size of a human hair. The researchers want to develop them on a nanoscale, which is about 1/1000 the width of a human hair, and then bundle many millions or even billions together to make a neuromorphic computing system. Such a honey-based system would be renewable and biodegradable – which, pardon the pun, would be really sweet.

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Honey holds potential for making brain-like computer chips

Photo, posted January 28, 2008, courtesy of Dino Giordano via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Americans And Lead Exposure | Earth Wise

April 4, 2022 By EarthWise Leave a Comment

Long-term exposure to lead can cause serious health problems, especially in children. Children are particularly vulnerable because their early years are characterized by rapid growth and brain development.

Lead is a powerful neurotoxin that can cause damage even at low levels of exposure. Lead poisoning can be acute, and can cause all sorts of health issues, including stomach pain, brain damage, and even death. Because lead accumulates in the body over time, lead poisoning can develop slowly. Exposure to lead can also contribute to a lower IQ and behavioral problems that can last a lifetime.

Lead is a naturally occurring element found in small amounts in earth’s crust. But as a result of human activities, lead can be found in all parts of the environment, including the air, soil, and water.

According to a new study recently published in the journal Proceedings of the National Academy of Sciences, approximately half of U.S. adults alive today were exposed to harmful levels of lead as children from the burning of leaded gasoline. The research team estimates that lead contamination has lowered those Americans’ IQ scores by more than two points on average.

In the study, the researchers used data on childhood blood-lead levels, leaded gasoline use, and population to gauge the lifetime exposure of every American adult in 2015. They found that more than 170 million Americans had exposure to concerning levels of lead as children. Those who grew up in the 60s and 70s, when the burning of leaded gasoline was at its peak, had the greatest exposure, losing up to six IQ points on average.

The legacy of lead exposure remains a persistent problem.

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