Scientists have unveiled a breakthrough tool that lets them identify fish by the sounds they make. By pairing spatial audio with 360° video, researchers have published the most extensive collection of fish sounds ever recorded, capturing a chorus that had remained largely unknown until now.
Milky seas are enormous patches of glowing ocean water. Unlike the quick flashes of light seen when waves or fish disturb bioluminescent plankton, milky seas shine with a steady, ghostly glow. They can cover tens of thousands of square kilometres—sometimes as large as entire countries—and last for days or even weeks.
Megalodon, the largest great predatory shark to have ever lived, dominated the oceans millions of years ago during the Neogene period. Despite its fame, much about its appearance and biology remains a mystery since its skeletons, made mostly of cartilage, are rarely fossilised. However, this new research offers valuable clues.
The Greenland shark, a giant species that can grow to more than five metres in length, has stunned scientists with its exceptional lifespan—estimated to last over 390 years, making it one of the longest-living vertebrates on Earth. Now, researchers are beginning to uncover the genetic secrets behind the Greenland shark's remarkable longevity.
The phylogenetic relationship of ctenophores (comb jellies) to other animals has been a source of long-standing debate.
Until recently, it was thought that Porifera (sponges) was the earliest diverging animal lineage, but recent reports have instead suggested Ctenophora as the earliest diverging animal lineage.
For the past 30 years, researchers have used whole-genome sequencing of organisms to advance their understanding of evolution.
In 2019, paleontologist Karma Nanglu from Harvard University received a finger-sized fossil. The specimen had originated from a fossil-rich stratum of Cambrian limestone in western Utah, and had been kept in a drawer at a Salt Lake City museum for years.
Upon hearing that there could be a very old tunicate, Nanglu expressed excitement interlaced with caution: "That's a group for which there is essentially no fossil record for the entire 500 million years of recorded history."
For more than two years, researchers on board the French expedition ship Tara sailed through the Pacific, stopping at almost 100 coral reefs to take thousands of water and coral samples. The expedition ended in 2018, and the analysis of the massive amount of data collected has taken five years.
Now, the initial results of the data analysis have been published. The findings should help us to better understand the living conditions of corals, to check their health status and to open up new possibilities for nature conservation.
— And the common feaures of decommissioned oil rigs, windfarms, wrecks and artificial reefs
Gliding slowly over the rocky reef, I was mesmerised, watching all the colourful reef fishes going about their daily activities. I was so entranced that I was startled to look up and find I was on a collision course with a massive stingray. This was the first stingray I had ever seen, and the giant creature terrified me. In the second it took my panicking brain to work out what to do, the stingray suddenly saw me and also got a shock.
Cetaceans were not limited by gravity in the buoyant marine environment and evolved multiple giant forms, exemplified today by the largest animal that has ever lived: the blue whale (Balaenoptera musculus).
There are tradeoffs, however, associated with large body size, including a higher lifetime risk of cancer due to a greater number of somatic cell divisions over time. The largest whales can have ∼1,000 times more cells than a human, with long lifespans, leaving them theoretically susceptible to cancer.
