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This Bird That Went Extinct 136,000 Years Ago Has Evolved Back Into Existence

Elias Marat

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Bird Went Extinct 136,000 Years Ago and Just Evolved Back Into Existence

In a rare case of a species effectively evolving into existence twice, the Aldabra rail has re-evolved back into existence after first going extinct 136,000 years ago, according to a new study.

Not only that, the flightless bird has also reclaimed its home island in the Aldabra Atoll in the Indian Ocean.

According to the study published May 8th in the peer-reviewed scientific journal Zoological Journal of the Linnean Society, the rail’s home in the atoll has been submerged multiple times throughout history during events that wiped out all the species that inhabited it.

However, the Aldabra rail has continued to return in a rare phenomenon known as iterative evolution, when the same ancestral lineage leads to the repeated evolution of a species at different points in time, producing parallel offshoot species that are nearly identical to one another and can pop up multiple times in various eras and locations—even when past iterations have gone completely extinct.

Such was the case with the Aldabra rail, having descended from a chicken-sized flying bird known as the white-throated rail, which faced its demise around 136,000 years ago when the island was completely inundated and submerged below sea level, wiping out all local fauna and flora.

As sea levels fell over the course of tens of thousands of years, however, fossil evidence has shown that the species once again re-colonized it. This time, the bird lost the ability to fly due to the absence of predators who once populated the island.

In a statement, lead researcher and avian paleontologist Julian Hume at the Natural History Museum said:

“These unique fossils provide irrefutable evidence that a member of the rail family colonized the atoll, most likely from Madagascar, and became flightless independently on each occasion. Fossil evidence presented here is unique for rails, and epitomizes the ability of these birds to successfully colonize isolated islands and evolve flightlessness on multiple occasions.”

This isn’t the first case of iterative evolution, which has also been observed in such animals as ammonites, sea turtles, and sea cows. Yet the two species of rail—the long-extinct iteration and the revived one—are the “most significant” case of avian iterative evolution ever found, the researchers concluded.

David Martill, a co-author of the study and paleobiologist at the University of Portsmouth, said:

“We know of no other example in rails, or of birds in general, that demonstrates this phenomenon so evidently. Only on Aldabra, which has the oldest palaeontological record of any oceanic island within the Indian Ocean region, is fossil evidence available that demonstrates the effects of changing sea levels on extinction and recolonization events.

Conditions were such on Aldabra, the most important being the absence of terrestrial predators and competing mammals, that a rail was able to evolve flightlessness independently on each occasion.”

With sea levels expected to rise in coming years, the modern flightless Aldabra rail may not fare much better than its ancestors. Indeed, with the very real possibility of extinction threatening the existence of over 1 million plant and animal species, odds are that the bird could face its demise yet again. But based on this study, a third iteration of the rail could perhaps return long after a potential deluge subsides.

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Scientists Say Species Throughout Earth’s History Keep Inexplicably Evolving Into Crabs

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A paper from 2017 recently resurfaced online and has gone semi-viral because of its weird, and, according to some scientists, somewhat disturbing/amazing conclusion: that life on Earth seems to naturally evolve toward crab-like species.

Originally published in the Biological Journal of the Linnean Society, the paper is titled “One hundred years of carcinization – the evolution of the crab-like habitus in Anomura.” It found a new life in mid-October on Boing Boing under the title “Animals have evolved into a crab-like-shape at least 5 separate times” and has since been the subject of articles on Popular Mechanics and several other websites.

So what are popular science writers – and their readers – so worked up about? The original paper discusses the curious and highly improbable sequence of instances involving convergent and parallel evolution of animals into crab-like species. These instances of carcinization – the scientific term for when a crustacean evolves from a non-crab-like form into a crab-like one – has happened at least five different times in completely different historical contexts.

In the paper, the researchers write:

“The fact that a crab-like habitus did not evolve solely in ‘true’ crabs but also several times independently in the Anomura makes this process ideal for evolutionary research.”

Parallel evolution is certainly no stranger to Earth’s history. For example, marsupials are commonly referred to in this context. Convergent evolution, which refers to species from independent epochs of time developing analogous morphological structures, is also well established by Darwinian principles. Species on separate evolutionary tracks of both habitat and time can end up arriving at the same traits and structures. However, the number of times it happens with the crab-like shape and features seems to baffle more than a few scientists.

Additionally, the researchers point out, the similarities are not just relegated to superficial appearances in shells and claws: the five evolutionary journeys toward carcinization include shared functional traits in neurological processes and circulatory systems.

“Curiously, not only did the crab-like habitus evolve independently from the ‘true’ crabs (Brachyura), it also evolved three times independently within anomurans. […] Although enormous morphological disparity is observed in the internal anatomy of the crab-like taxa, reflecting the fact that the evolution of the crab-like habitus was indeed convergent, various corresponding dependences are found across the different lineages between the external characters of a crab-like habitus/morphotype and inner structures. In other words, as a result of carcinization certain structural coherences led to the specific internal anatomical patterns found in crab-like forms.”

So, what does it all mean? Is life on Earth somehow predisposed to crabs? Does this mean that when we meet aliens someday they will be giant intelligent crabs? Or could there be some strategic evolutionary advantage in the crab-like habitus and internal structures?

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7 Arrested In Florida For Trafficking Flying Squirrels

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At least seven people are facing numerous criminal charges after they were caught trafficking flying squirrels. According to investigators, their operation was worth an estimated $1 million.

In a statement on Monday, the Florida Fish and Wildlife Conservation Commission (FWC) said that the suspects have been charged with racketeering, money laundering, scheming to defraud, and other organized criminal laws involving “an elaborate organized enterprise to smuggle Florida’s wildlife to interstate and international buyers.”

The agency says that in January of 2019, they received a complaint from a concerned citizen about flying squirrels being illegally trapped in a rural part of Marion County. Flying squirrels are considered a protected wild animal in Florida, but they are illegally sold internationally because their rarity fetches such high prices.

After receiving the initial complaints, the FWC began a 19-month investigation where they tracked the hunters and monitored their international operation. The investigators found that once the poachers captured the squirrels, they sold the animals to a wildlife dealer in Bushnell and were laundered through the licensed business of the dealer, who claimed they were captive-bred, which would have made them legal to sell.

The poachers set out an estimated 10,000 squirrel traps throughout central Florida and investigators tracked as many as 3,600 flying squirrels being captured by the group in less than three years.

It is not clear how the agency estimated the operation to be worth $1 million, because the dealer involved in the scheme only received an estimated $213,800 in gross sales in the three years that he was being monitored.

The wildlife dealer was selling the animals to buyers from South Korea who traveled to the United States specifically for the squirrels. The buyers would then take the animals to Chicago, where they were sent to Asia by a wildlife exporter who was unaware of the plot. The investigation into the flying squirrels revealed that the same group was trafficking a variety of other poached animals, including protected freshwater turtles and alligators. There were also dealers and traffickers in Florida and Georgia dealing with the group. However, the operation was meticulous and careful, and many of the people involved with the scheme did not even know each other.

Maj. Grant Burton, FWC Investigation’s section leader, said that the poachers were a danger to the state’s wildlife.

“Wildlife conservation laws protect Florida’s precious natural resources from abuse. The concerned citizen who initially reported this activity started an investigation that uncovered a major smuggling operation. These poachers could have severely damaged Florida’s wildlife populations,” said Maj. Burton.

The life expectancy of flying squirrels in the wild is about six years, but flying squirrels can live up to fifteen years in zoos. The mortality rate in young flying squirrels is high because of predators and diseases. Predators of flying squirrels include tree snakes, raccoons, owls, martens, fishers, coyotes, bobcats, and feral cats. In the Pacific Northwest of North America, the northern spotted owl (Strix occidentalis) is a common predator of flying squirrels. Obviously, poachers also represent a serious threat to the species.

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More than 5,000 baby seals wash up on Namibia beach in unprecedented die-off

Elias Marat

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Thousands of dead seal pups have washed ashore on the coast of Namibia, raising grave concerns from conservationist groups.

Locals were in shock after an estimated 5,000 premature cape fur seal pups washed up along the coast of Pelican Point peninsula, turning the popular tourist destination known for its thriving schools of dolphins and seal colonies into a pup graveyard.

Cape fur seals are often referred to as the “dogs of the ocean,” owing to their playful nature and abundant energy. However, the seals are known to desert their young or suffer miscarriages when food supplies are scarce.

The unprecedented die-off of the 5,000 Cape fur seals is now being probed by the country’s fisheries ministry, reports Bloomberg.

Nearly all were born prematurely before quickly dying, according to marine biologist Naude Dreyer of  Ocean Conservation Namibia.

“When the pregnant female feels she does not have enough reserves, she can abort,” he explained. “A few premature deaths is a natural event, but thousands of premature dead pups is extremely rare.”

Dreyer noticed the masses of dead seal pups while flying his drone over the Pelican Point seal colony on Oct. 5.

“This is the situation at Pelican Point, Namibia,” his non-profit group wrote in a Facebook post. “All the little red circles mark dead seal pups. A rough estimate brings the numbers to more than 5,000 at our seal colony alone. This is tragic, as it makes up a large portion of the new pup arrivals expected in late November.”

This is the situation at Pelican Point. All the little red circles mark dead seal pups. A rough estimate brings the…

Posted by Ocean Conservation Namibia on Tuesday, October 13, 2020

The seals are commonly found across the southern Atlantic coastlines of the African continent, spanning Namibia and South Africa to the southern tip of Angola.

“Normally cape fur seals would give birth from mid-November until early December,” Dr. Tess Gridley told Africa News.  “That’s the height of pupping that we would normally expect but what has been happening this year is there has been an increase in abortions that was first seen starting in August and really sort of peaked just last week in October.”

However, female cape fur seals are increasingly appearing emaciated and starving, raising alarm among conservationists about the long-term health of the typically thriving seal population.

 “There are about 1.7 million cape fur seals in total and about a million of those are actually in Namibia so in terms of the overall number of animals, they are quite resilient to these effects,” Gridley explained.

“But one issue that we do think might happen in the future is you will see a dip in reproduction potentially going forward particularly now for those animals that have unfortunately died,” she continued. “They are not going to be recruited into the population, so you might see a localized effect at the Pelican Point colony and also we are trying to monitor to see whether there is a wider scale impact that might affect other colonies as well.”

An absence of fish in the region and the spread of disease and toxins in the water are among the possible reasons behind the die-off. 

“The seals look a bit thin and it could likely be caused by a lack of food,” Dreyer said. “Other seal colonies at other beaches look much better and they do not record the same amount of premature pups.”

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