With Whale Sharks, Males Grow Faster, But Females Grow Bigger
New research has provided surprising details about the biology of Earth's largest fish, the whale shark. Scientists say that female whale sharks grow more slowly but reach a much larger size than males.
Researchers recently said they had followed the growth of 54 whale sharks over 10 years. The creatures swam in the Ningaloo Reef off of Australia's west coast, where hundreds of the rare fish travel every year.
Whale sharks of both sexes were found to have their fastest growth while young — about 20 to 30 centimeters per year.
Males were found to grow faster than females. They reached around eight meters in length at about 30 years old. At that age, they reach sexual maturity, meaning the fish were able to produce young. Females grew larger than males. Females reached about 14 meters at about age 50, when they reached sexual maturity.
Mark Meekan is a marine biologist at the Australian Institute of Marine Science. He led the research that was published in Frontiers in Marine Science.
Meekan described whale sharks as "remarkable." He noted that females give birth to many young: "up to 300 at one time." For this reason, Meekan said, female sharks probably need to be very large.
"Our study provides the first evidence that male and female whale sharks grow at different rates," Meekan said.
Whale sharks are filter feeders, meaning they take food and nutrients from the water. They swim great distances to find enough to eat.
The longest-known whale shark ever recorded reached a length of about 18 meters. Whale sharks can live for 100 to 150 years.
Meekan suggested the study's findings were important for saving whale sharks. He noted that if it takes 30 or more years for the creatures to reach sexual maturity, "there are lots of threats such as hunting and ship-strike...before they get a chance to breed."
For that reason, Meekan described efforts to save the creatures as "urgent."
I'm John Russell.
1.biology n. 生物
We dissected a frog in biology class.
2.effort n. 努力；成就
Finding a cure requires considerable time and effort.
His behaviour spoke of an early maturity.
Each is only about a centimeter long.
5.He noted that females give birth to many young: "up to 300 at one time."
at one time 一次；一度
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Can you handle several things at one time?
6.For this reason, Meekan said, female sharks probably need to be very large.
For this reason 为此
For this reason, we never have it all.
For this reason, I am advising you to reconsider your choice.
新研究提供了关于地球上最大鱼类鲸鲨生物学方面令人意外的细节 。科学家表示，雌性鲸鲨的生长速度较慢，但是体型比雄性鲸鲨更大 。
研究人员最近表示，他们在10年时间里追踪了54头鲸鲨的生长情况 。这些生物在澳大利亚西海岸的宁格鲁礁游动，每年有数百种珍稀鱼类在这里游动 。
人们发现，雄性鲸鲨比雌性鲸鲨的生长速度更快 。它们在30岁左右身长能达到8米 。它们在这个年龄达到性成熟，这意味着它可以繁殖后代 。雌性鲸鲨的体型比雄性鲸鲨大 。雌性在50岁左右时达到性成熟，身长能够达到14米 。
马克·米肯（Mark Meekan）是澳大利亚海洋科学研究所的海洋生物学家 。他领导了这项研究，该研究结果发表在《海洋科学前沿》上 。
米肯称，鲸鲨“很了不起 。”他指出，雌性鲸鲨会繁殖很多幼鲨，一次最多能分娩300只 。米肯表示，出于这个原因，雌性鲸鲨可能需要更大的体型 。
鲸鲨是滤食者，这意味着他们从水中获取食物和营养 。它们会游很远的距离，寻找充足的食物 。
有记录以来最长的鲸鲨身长达到了约18米 。鲸鲨可以生存100到150年 。
米肯认为，这项研究对挽救鲸鲨至关重要 。他指出，如果这些生物达到性成熟需要30年或更长时间，“那么在有机会繁殖之前他们会面临许多威胁，例如捕猎和撞船 。