琥珀中的螃蟹揭示了從海洋到陸地的演化
An ancient creature found in amber may reveal a critical point in the evolutionary history of one of Earth’s most versatile animals: crabs. This 100-million-year-old fossil, discovered in Myanmar, is helping researchers resolve a prehistoric puzzle about when crabs started to move away from the seas.
在琥珀中發現的一種古代生物可能揭示了地球上最多才多藝的動物之一螃蟹進化史上的一個關鍵時刻。這塊在緬甸發現的1億年前的化石，正在幫助研究人員解決一個史前謎題:螃蟹是何時開始離開海洋的
Amber:琥珀
Versatile: 多種功能的
The tiny crab’s preservation is spectacular. Researchers were able to see details of the animal’s jointed legs, claws, compound eyes, and even its gills through the amber.
小蟹的儲存是驚人的。研究人員能夠透過琥珀看到這種動物的關節腿、爪子、複眼甚至腮的細節。
Preservation: 保護
Spectacular: 令人驚歎的
Scientists are unsure whether the new fossil represents an adult crab or a juvenile, but the crab is so well preserved that people were able to determine that the creature is a new species.
科學家們尚不確定這塊新化石代表的是成年螃蟹還是幼年螃蟹，但這種螃蟹儲存得如此完好，以至於人們能夠確定這種生物是一個新物種。
Juvenile: 青少年
Amber is fossilized tree resin, making it all the more surprising to find a crustacean encased inside. Finding a crab in amber is like finding a needle in a haystack.
琥珀是一種樹脂化石，所以當人們發現裡面有甲殼類動物時，就更加驚訝了。在琥珀裡找螃蟹就像大海撈針。
Resin: 樹脂
Haystack: 乾草堆
The study team proposes that the crab could represent the oldest known land crab, holding clues about how crabs made the evolutionary jump from the sea to inland environments.
研究小組提出，這種蟹可能是已知的最古老的陸地蟹，併為蟹類如何從海洋進化到內陸環境提供了線索。
The condition of the amber and other clues are just as revealing as the little arthropod inside. The crab is intact, rather than an empty shell left over from molting, suggesting the animal truly did live in the habitat where it became preserved. The lack of sand grains in the amber, and the way the sap flowed over the crab, also hint that this fossil came from an environment away from the beach—likely a freshwater environment.
琥珀的狀況和其他線索就像裡面的小節肢動物一樣能說明問題。這隻蟹是完整的，而不是蛻皮後留下的空殼，這表明這種動物確實生活在它被儲存下來的棲息地。琥珀中缺少沙粒，以及汁液流過螃蟹的方式，也暗示了這塊化石來自於一個遠離海灘的環境——可能是淡水環境。
Arthropod: 節肢動物
Intact:完好無缺的
Grain: 粒狀物
Sap: 樹的流液
Moving away from the ocean was a big step for crabs. Becoming adapted to life in fresh water isn’t as simple as throwing a switch. The animals had to change the way they breathed, regulated water, and kept from drying out.
離開海洋對螃蟹來說是一大步。要想適應淡水生活，可不是按一下開關那麼簡單。動物們必須改變呼吸方式，調節水分，避免乾燥。
The largest barrier has to be how an organism manages water and electrolytes like salt in its body. Nevertheless, crabs have moved inland from the seas over and over again. Modern crabs not only live on the beach, among coral reefs, and in the ocean depths, but can also be found in rivers and lakes.
最大的障礙是生物體如何管理體內的水和電解質(如鹽)。儘管如此，螃蟹還是一次又一次地從海洋遷移到內陸。現代的螃蟹不僅生活在海灘、珊瑚礁和海洋深處，而且在河流和湖泊中也能找到。
Organism: 有機體
Electrolyte: 電解質
