新华网/日前，科学家们揭示出了龙虾“年轮”的奥秘，据中新网的报道称，人们知道如何判断鱼和扇贝的年龄，但对于如何判断龙虾的年纪感到不解。如今，科学家也终于知道龙虾的真实年龄“藏”在何处了。
英国渔民捕获到的巨型龙虾，体重将近6公斤
据悉，根据对龙虾“年轮”的判断，科学家可以掌握其真实年龄，事实上，龙虾年纪的奥秘藏在它们的眼柄(eyestalk)和胃里，由于它们的年轮长在这些不易被发觉的地方，所以人们一般不知道龙虾活了多久。
科学家称，鱼的寿命可从它们内耳的年轮中得知，扇贝的年纪可从其外壳上的年轮中读出。而龙虾的年轮长得位置比较特殊，故而长时间以来人们无法准确判定它们到底活了多久。
此前，英国的几个渔民曾在德文郡的比格伯里湾与霍普湾之间的水域捕获到了一只体型巨大的龙虾，其身长约为81厘米，重达5.88公斤，为近80年以来在英国海域所捕捞到的龙虾中个头最大的一只。但是人们无法准确的判断这只龙虾的年龄，只是依据体型来看应该至少有20岁，也许有30多岁甚至可能超过100岁。
http://news.xinhuanet.com/yzyd/tech/20121203/c_113886639.htm?prolongation=1
How old is a lobster? Check his eyestalk
The age of a lobster, or a crab or shrimp, can be determined by counting growth rings, as is done with trees. But scientists aren’t sure yet how old a lobster can live to be.
By Clarke Canfield, Associated Press / November 30, 2012
Scientists have now figured out that growth rings can be found in the eyestalk – a stalk with an eyeball on the end. Growth rings are also found in gastric mills – the teeth-like structures in their stomachs used to grind up food. (AP Photo/Robert F. Bukaty)
PORTLAND, MAINE
For the first time, scientists have figured out how to determine the age of a lobster — by counting its rings, like a tree.
Nobody knows how old lobsters can live to be; some people estimate they live to more than 100.
But knowing — rather than simply guessing — their age and that of other shellfish could help scientists better understand the population and assist regulators of the lucrative industry, said Raouf Kilada, a research associate at the University of New Brunswick who was the lead author of a scientific paper documenting the process.
Before now, scientists deduced a lobster’s age judging by size and other variables. But it’s now known that lobsters and other crustaceans, such as crabs and shrimp, grow one ring per year in hidden-away internal spots, Kilada said.
RECOMMENDED: Are you scientifically literate? Take the quiz
“Having the age information for any commercial species will definitely improve the stock assessment and ensure sustainability,” he said after presenting his findings Thursday at a scientific conference in Portland.
Scientists already could tell a fish’s age by counting the growth rings found in a bony part of its inner ear, a shark’s age from the rings in its vertebrae and a scallop or clam’s age from the rings of its shell.
But crustaceans posed a problem because of the apparent absence of any permanent growth structures. It was thought that when lobsters and other crustaceans molt, they shed all calcified body parts that might record annual growth bands.
For their research, Kilada and five other Canadian researchers took a closer look at lobsters, snow crabs, northern shrimp and sculptured shrimp.
They found that growth rings, in fact, could be found in the eyestalk — a stalk connected to the body with an eyeball on the end — of lobsters, crabs and shrimp. In lobsters and crabs, the rings were also found in the so-called “gastric mills,” parts of the stomach with three teeth-like structures used to grind up food.
To find the growth bands, the scientists dissected the eyestalks and the gastric mills, cut out sections and viewed them under microscopes.
Lobsters don’t lose reproductive capabilities or organ functions or exhibit signs of aging as they get older, but nobody knows for sure how old they can live to be.
“We’ve thought lobsters could live to 100 years old, and this new aging technique will be a way to document that,” said Bob Bayer, executive director of the University of Maine’s Lobster Institute.
The paper was published in this month’s Canadian Journal of Fisheries and Aquatic Sciences, a well-regarded peer-reviewed scientific journal based in Ottawa, Ontario, that has been published since 1901. Kilada’s was one of more than 50 scientific presentations at the conference, attended by more than 100 lobster scientists from the U.S., Canada and Europe.
Bayer agreed that this is the first time scientists have a direct method to place an age on crustaceans.
“Right now we’re just guessing at their age,” he said.
Kilada said he saw lobster specimens that were 16 or 17 years old during his research. He estimates that there are lobsters 60 or 70 years old living in the wild.
Susan Waddy, a lobster researcher with Canada’s Department of Fisheries and Oceans, said she has kept lobsters in her laboratory that are more than 30 years old. She suspects they live to be 40 or 50.
“We know they don’t live forever,” she said.
http://www.csmonitor.com/Science/2012/1130/How-old-is-a-lobster-Check-his-eyestalk
That Lobster is How Old?!
Monday, December 10, 2012 by Rachelle Pinault
How big was the largest lobster you have ever seen? Did you wonder how old it might be? I have seen a 27pound lobster, and he was estimated to be about 50 years old! Up until now, scientists could only estimate a lobster’s age by its size, which has not been a very precise method.
On Thursday November 29th at a scientific conference in Portland, Maine, Raouf Kilada, a research associate from the University of New Brunswick, announced that he and five other scientists discovered a way to accurately age a lobster!! It may sound very strange, but the proof is in the lobster’s eyes!!
Lobsters have eyestalks. An eyestalk is like a rod that is connected to the lobster’s body at one end and has an eyeball at the other end. The scientists discovered that there are growth rings within the eyestalks that can be counted to determine the lobster’s age! This process is a little like aging a tree by counting the rings in the trunk!
This is a very important discovery that will allow scientists to better assess lobster populations, and determine exactly how old a lobster can live to be. Some scientists believe they can live for well over 100 years! Stay tuned… we may have the answer soon…
If you would like to read more, here is a link to one news article about this story: http://www.huffingtonpost.com/2012/11/30/lobster-age_n_2215990.html
http://mystery.gmri.org/blog/blog-details.aspx?ID=44
How old do lobsters get?
Answer:
Lobsters, when not caught, can live for a long time. Living to the age of 100 is not uncommon. Of course, because lobsters are prized for their meat, many don’t make it past just a couple of years old. Lobsters must be a certain length — not age — to be deemed legal for catching. 15 yrs. old
It takes approximately seven years (depending on the water temperature) for a lobster to grow to legal harvesting size (1-1 1/4 lb.). After that, a lobster will grow about 1 pound for every 3 years.
It is interesting to note that lobsters show no real signs of aging, other than growing. They actually can reproduce and stay fertile continuously!
The secret lies in their telomeres.
telomeres are found at the end of chromosomes for all living creatures. As we age and cells divide, the telomeres shorten and eventually disappear- leading to aging and death.Lobsters telomeres take a much longer time to shorten , if at all- allowing them to ‘maintain their youth’ (A lot of anti-aging experimants are done with lobsters)
http://wiki.answers.com/Q/How_old_do_lobsters_get
