The best of EcoWatch, right in your inbox. Sign up for our email newsletter!
Starfish Make Comeback After Mysterious Melting Disease
Starfish appear to be making a stunning comeback in the West Coast after a mysterious "melting" disease decimated their numbers five years ago.
The invertebrates that survived the die-off developed a genetic resistance protecting them from the pathogen, a new study published in the Proceedings of the National Academy of Sciences has found.
The disease that plagued them, also known as sea star wasting syndrome, featured grisly symptoms where the sea stars would lose legs, disintegrate and ultimately die. The outbreak was first discovered in 2013 and eventually caused the death of millions of sea stars in the West Coast.
The species most heavily affected by the disease was the Pisaster ochraceus, or ochre star. More than 80 percent fell victim to the pathogen. As a "keystone" predator, its loss could have disrupted the entire marine intertidal ecosystem.
The leg of this purple ochre sea star in Oregon is disintegrating, as it dies from sea star wasting syndrome. Photo taken in May 2014Elizabeth Cerny-Chipman/ Oregon State University / Flickr / CC BY-SA 2.0
But the new study revealed a 74-fold increase since 2013 in the number of surviving offspring of the ochre star, the San Francisco Chronicle reported.
The researchers compared the DNA of ochre stars before and after the outbreak and found that the juveniles thriving today have developed a gene that resists the virus.
"This revealed consistent changes between the original population and survivors, between the original population and new juveniles, and across geographic locations," Lauren Schiebelhut, a University of California, Merced biologist and lead author of the study, told the Chronicle. "Subsequent generations will be the progeny of survivors and so we expect the genetic shift to be maintained."
The cause of sea star wasting syndrome is still not known, but previous studies have linked the sea stars' risk of becoming infected with the disease due to warmer ocean temperatures. Notably, the current study brings hope that some marine species could quickly evolve resilience to the effects of climate change.
The starfish that survived the epidemic are living examples of natural selection in process, as Michael Dawson, a UC Merced professor and co-author of the study, explained to the Chronicle.
"That ochre sea stars had the capacity to adapt to events as dramatic as this is remarkable, and perhaps re-assuring that future climate change may be withstood by some species," Dawson added. "But the ochre sea star is perhaps a species with greater resilience than many, and with projected climate swings expected to be more extreme, the ochre sea star's resilience is perhaps a small, distant bright light on a pretty stormy sea."
EcoWatch Daily Newsletter
In 2018, there were about 5 million electric cars on the road globally. It sounds like a large number, but with well over a billion cars worldwide, electric vehicles are still only a small percentage.
By Byron Reeves, Nilam Ram and Thomas N. Robinson
There's a lot of talk about digital media. Increasing screen time has created worries about media's impacts on democracy, addiction, depression, relationships, learning, health, privacy and much more. The effects are frequently assumed to be huge, even apocalyptic.
By Raphael Tsavkko Garcia
Rarely has something so precious fallen into such unsafe hands. Since Jair Bolsonaro took the Brazilian presidency in 2019, the Amazon, which makes up 10 percent of our planet's biodiversity and absorbs an estimated 5 percent of global carbon emissions, has been hit with a record number of fires and unprecedented deforestation.
Microsoft announced ambitious new plans to become carbon negative by 2030 and then go one step further and remove by 2050 all the carbon it has emitted since the company was founded in 1975, according to a company press release.