第1804期:Scientists Learn What Killed Caribbean Sea Urchins

Scientists say a small parasite is the cause of death of many sea urchins in the Caribbean Sea. Sea urchins are simple animals that have long spines. Last year, the long-spined sea urchins, also known as Diadema antillarum, started getting sick. They were losing their spines and their sticky feet were losing their grip on the coral reefs. The loss of so many sea urchins, which eat algae that grow on the corals, affected the undersea environment from the Virgin Islands to Puerto Rico to Florida. Mya Breitbart led a team of scientists who investigated the sickness. She is a marine microbiologist at the University of South Florida.科学家说，一种小型寄生虫是加勒比海许多海胆死亡的原因。海胆是具有长刺的简单动物。去年，长刺海胆（也称为 Diadema antillarum）开始生病。他们正在失去脊椎，黏糊糊的脚正在失去对珊瑚礁的抓地力。大量以生长在珊瑚上的藻类为食的海胆的消失影响了从维尔京群岛到波多黎各再到佛罗里达的海底环境。 Mya Breitbart 领导了一个研究这种疾病的科学家团队。她是南佛罗里达大学的海洋微生物学家。The team presented their study recently in the scientific publication Science Advances. “The case is closed,” Breitbart said. The scientists compared the sick urchins to healthy ones and determined a single-celled parasite was to blame. Ian Hewson is a marine disease researcher at Cornell University in the state of New York. He said the team ruled out bacteria or viruses. But the team did see single-celled organisms called ciliates in the sick urchins.该团队最近在科学出版物《科学进展》中介绍了他们的研究。 “案件已经结案，”布赖特巴特说。科学家们将患病的海胆与健康的海胆进行了比较，并确定单细胞寄生虫是罪魁祸首。伊恩·休森 (Ian Hewson) 是纽约州康奈尔大学的一名海洋疾病研究员。他说该团队排除了细菌或病毒。但研究小组确实在患病的海胆中发现了一种叫做纤毛虫的单细胞生物。The scientists then put a group of healthy sea urchins grown in a laboratory in a tank with some of the parasites. Six of the 10 urchins in the tank later died. The scientists are now working to find a way to prevent future losses. They do not have a treatment for the sea urchins, but they are hoping to learn how the parasites spread so they can stop them. Breitbart noted another time that many sea urchins died in the 1980s. She did not know if the same parasites caused that problem. Don Levitan is a marine scientist at Florida State University who was not involved in the study. He said the two urchin die-offs, or widespread losses of the animals, have changed the coral reefs in the Caribbean Sea. He said at one time, they were covered with spiny urchins, but now they are covered in algae, sick from disease and stressed by rising water temperatures. “Coral reefs in the Caribbean are in trouble,” he said. “We are at a different place than we were 30, 40 years ago.”然后，科学家们将一组在实验室中生长的健康海胆放入装有一些寄生虫的水箱中。水箱里的 10 个顽童中有 6 个后来死了。科学家们现在正在努力寻找一种方法来防止未来的损失。他们没有治疗海胆的方法，但他们希望了解寄生虫是如何传播的，这样他们就可以阻止它们。 Breitbart 另一次指出，许多海胆在 80 年代死亡。她不知道是否是同样的寄生虫引起了这个问题。 Don Levitan 是佛罗里达州立大学的海洋科学家，他没有参与这项研究。他说，两次海胆的死亡，或者说这种动物的广泛灭绝，已经改变了加勒比海的珊瑚礁。他说，曾几何时，它们长满了刺海胆，但现在它们长满了藻类，因疾病而生病，并因水温升高而感到压力。 “加勒比地区的珊瑚礁陷入困境，”他说。 “与 30、40 年前相比，我们处在一个不同的地方。”