Latest news with #CetAsiaResearchGroup
CBC
02-05-2025
- Science
- CBC
Wild fish can tell us apart, and more...
The 'bone collector' caterpillar covers itself with body partsIt's like something from a horror movie. A creeping, carnivorous creature that in a macabre attempt at disguise and protection, covers itself with the dismembered remains of dead insects. This super-rare caterpillar is one of the strangest insects in the world. It lives on spider webs inside of trees and rock crevices in a 15 square kilometre radius on the Hawaiian island of O'ahu. Daniel Rubinoff, from the University of Hawaii Insect Museum, found about 62 of these caterpillars over the past 20 years. Their research was published in the journal Science. If a dolphin pees in the water, does anybody know it?Researchers observing river dolphins in Brazil were first surprised to see the animals turning on their backs and urinating into the air, and then further amazed to see other dolphins sampling the falling stream. The Canadian and Brazilian team, led by Claryana Araújo-Wang from the CetAsia Research Group, believe this aerial urination may be a way to communicate dominance among males. The research was published in the journal Behavioural Processes. How the snowball Earth made life bloom on our planet700 million years ago our planet was frozen from pole to pole during a period known as snowball Earth. Glaciers at that time scoured deep into the continents below like a giant bulldozer, grinding the rock into fine sediments. In a new study in the journal Geology, scientists found that as the glaciers melted, a lot of that loose material was injected very rapidly into the oceans. Branden Murphy, from St. Francis Xavier University, said this chemical cocktail fertilized the oceans, and set the stage for rise of multicellular complex life on Earth. How a team of microbiologists use cars to sample air across the countryUnderstanding the distribution of bacteria that might be a concern for human or animal health across an entire country is a huge job. But a team from Laval used a very clever shortcut to gather their data. They collected car air filters from vehicles across the nation, and looked in them to see what they sucked up. They found regional differences in the antimicrobial resistance genes specific to the agricultural activities and environmental factors at each location. Paul George, from Laval University, was the lead researcher on the study published in the journal Environmental DNA. Albertan obsidian artifacts are the end point of a widespread Indigenous trade networkObsidian — volcanic glass used to make super-sharp tools — is found as artifacts from chips to blades to arrowheads at hundreds of sites across the Rockies of Alberta and B.C., dating back thousands of years. However, there are no volcanos in the area so archaeologists are using this volcanic glass to chart Indigenous trade routes through North America. New research, led by Timothy Allan of Ember Archeology, has traced the obsidian's point of origin to a site nearly 1,000 kilometres away, suggesting the material travelled over long distances and passed through many hands. The research was published in the Journal of Field Archaeology. Do his gills ring a bell? Fish can recognize humansScientists at a Mediterranean research station kept noticing that particular fish would follow them around whenever they would try and do experiments. To find out if the fish were actually capable of recognizing individual humans, a team from the Max Planck Institute of Animal Behavior in Germany decided to turn this annoying behaviour into a scientific experiment. They found that the fish were indeed capable of remembering which humans had shared tasty treats in the past. The research was published in the journal Biology Letters.
Yahoo
31-01-2025
- Science
- Yahoo
Male Amazon river dolphins pee into the air, confusing scientists
Researchers say they have made a startling discovery in the Amazon River. But their evidence wasn't collected from the water—it could be seen from shore. After around 219 hours of observations, they can confirm that male Amazon river dolphins (Inia geoffrensis), also known as botos, often roll onto their backs and urinate over three feet into the air. It isn't random. The male botos appear to be peeing with a purpose. Over four years, a team from Canada's CetAsia Research Group traveled to the Amazon river, where they then closely watched river dolphin social interactions. Researchers documented a total of 36 separate instances of male botos deciding to pee while floating in the unconventional position. The findings, presented in a recent study published in the journal Behavioural Processes, support rare, anecdotal stories of past boto behavior. 'Aerial urination starts with a boto slowly positioning itself upside down, exposing its penis above water, and ejecting a stream of urine into the air,' the team explained in their study. What's more, another male dolphin was swimming nearby about two-thirds of the time, and often approached the urine stream as it landed in the water about three feet away. They sometimes waited in place, but in other instances, they even pursued the pee trajectory using their snout, or rostrum.'We were really shocked, as it was something we had never seen before,' study author Claryana Araújo-Wan recounted to New Scientist on January 31st. Urine is a common communication tool used by many terrestrial animals such as dogs, bears, and cats. It's seen far less frequently in aquatic environments, but Araújo-Wan and their colleagues offered a few examples in their study. Dominant male African cichlid fish (Astatotilapia burtoni) interpret urine pulses for both reproductive and territorial information. The narrow-clawed crayfish (Astacus leptodactylus), meanwhile, urinates as a sign of aggression. In both of these cases, however, it's more about the act of peeing than what is actually in the pee itself. This makes the boto behavior all the more interesting, according to researchers. Dolphins lack a strong sense of both smell and taste, so it's still somewhat unclear how they are interpreting the urine streams. The study's authors hypothesized that the male Amazon river dolphins may rely on their rostrum bristles to interpret their fellow boto's urine composition, such as hormonal content indicating physical health and social position. A previous study from a team at Stephen F. Austin State University in Texas confirmed bottlenose dolphins (Tursiops truncates) use their tongues to identify other cetaceans through the taste of their urine. Knowing this, it's also possible that botos in the Amazon may engage in similar activities. But all that still doesn't explain why the botos are firing pee streams into the air. Researchers conceded that 'aerial urination likely serves a social function beyond waste elimination,' but stopped short of landing on any definitive reason beyond possible 'social or communicative functions.' Given their heightened ability to sense acoustical signals, it may be that the aerial urine alerts dolphins to check it out as it hits the water. Regardless of the actual reason, confirming the unique behavior among Amazon river dolphins now opens up the possibility for future study. With more time—and more pee—researchers may eventually learn much more about the aquatic mammal's complex social dynamics.
