Longest and shortest
life spans
 Q: Which animal has longest and which the
shortest life span?
The short-lived gastrotrich. Courtesy of Jasper Nance and
Wikipedia.
A: The giant tortoise
lives the longest, about 177 years in captivity, and the gastrotrich (a minute
aquatic animal) lives the shortest — three
days.
This question brings up intriguing matters, such as: what is
an animal, can we compare all animals together, when does life begin and end,
what can we actually observe? Here are some answers:
Animals are living things that aren't plants. Animal cells lack cellulose walls
and chlorophyll. Animals can't photosynthesize to eat; they need more complex food, like
proteins. They move around when they want to and respond quickly if poked or otherwise
stimulated.
Protozoans are animals, but can we include such animals in our
search for extreme life spans? No, because protozoans reproduce by dividing a single parent.
They are not individuals and essentially live forever, or as long as the species
survives. We can't compare colonies or genetically identical organisms with
distinct individuals that result from a sexual reproduction. That's comparing
apples with oranges.
Certain fishes and reptiles apparently keep on growing for
extended lives unless some accident
befalls them. Is one of them the oldest animal? Maybe. But, such animals live in the wild. We
can't observe them for the length of time it takes to determine their eventual life span. Animals
move around, which makes evaluating their age difficult. We determine species life spans usually
from captive animals because we can track their ages.
So, that's how I arrived at the answer--from animals in captivity. The longest-lived captive
animal is the giant tortoise (177 years) and the shortest, the gastrotich (3 days).
By the way, Forest Preserve District of Cook County
presents examples of extreme old age in a nature bulletin (No. 486-A, dated
March 24, 1973). Here's their animal old age table, chosen from reliable
records of zoos and aquariums all over the world:
MAMMALS YEARS
Elephant 69
Horse 50
Hippopotamus 49
Chimpanzee 40
Grizzly Bear 32
Bison 30
Lion 30
Tiger 25
Elk 22
Mountain Lion 20
Beaver 19
Wolf 16
Squirrel 16
Chipmunk 12
Cottontail 10
House Mouse 4
|
BIRDS YEARS
Turkey Buzzard 118
Swan 102
Parrot 80
Great Horned Owl 68
Eagle 55
English Sparrow 23
Canary 22
Humming Bird 8
|
FISH YEARS
Catfish 60
Eel 55
Carp 47
Mosquitofish 2
|
REPTILES YEARS
Giant Tortoise 152
Box Turtle 123
Alligator 68
Snapping Turtle 57
Cobra 28
Cottonmouth 21
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AMPHIBIANS YEARS
Giant Salamander 55
Toad 36
Bullfrog 30
Mud Puppy 23
Green Frog 10
Newt 7
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INSECTS YEARS
Cicada 17
Ant (queen) 15
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Finally, a Danish study of 3000 dogs indicated that the median life span of
all dogs in the study was 10 years, reported Helle Friis Proschowsky, an animal
scientist at Denmark's Royal Veterinary and Agricultural University and the
Danish Kennel Club. Mixed breed canines generally lived for another year, dying
at a median age of 11 years. Smaller breeds generally lived longer than
bigger ones. (Answered April 4, 2001)
Comment
I'll post your comment with the discussion as soon as I
can. Readers' Comments
- Why aren't Tuararas on your list? It would seem they would be right up at
the top of longest lifespan. Tuataras reach sexual maturity at 20 and
can live to between 150 and 250 years. Michael,
Oakland, California, USA
Reply: Good point. The tuatara
is the only living descendent of the order of reptiles (Rhynchocephalia) that
flourished a few hundred million years ago, and now lives in the cold, damp
climate of about 30 small islands off the coast of New Zealand. This
18-inch (50-cm) long lizard-like reptile takes about two years to hatch and 10
to 20 years to reach sexual maturity (the longest reproductive cycle of any
reptile). "It's not uncommon for an individual to live for over 100
years, says Bruce Musico of the University of Michigan's Animal Diversity Web.
- Dogs can live longer. Actually the longest living
animal is a clam. It's a sea animal that can live up to 400 years. Also,
you have written that dogs can live up to 10 years, whereas my dog lived for
13. Ash, Lahore, Pakistan.
- Add bowhead whales to your list of longer lived Mammals. "In
May 2007, a 50 ton specimen caught off the Alaskan coast was discovered to
have the head of an explosive harpoon embedded deep under the blubber of its
neck. Examination determined the 3 1/2 inch arrow-shaped projectile was
manufactured in New Bedford, Massachusetts, a major whaling center, around
1890. This proof that it survived a similar hunt more than a century ago
indicated to researchers that the whale's age was between 115 and 130 years
old.
Because of their possible lifespans, female Bowhead Whales are believed to go
through menopause. Observations of very large animals without calves support
this hypothesis.
Plainly, maximum lifespan is not yet determined - but it may be the greatest
of all mammals." From:
http://en.wikipedia.org/wiki/Bowhead_Whale See p 77, April 2009
National Geographic for description as the "longest lived mammal on the
planet" Dawson, Nashville, Tennessee, USA
- Don't forget Mayflies. I was under the impression that the
Mayfly only lives for 1 day which would give it the shortest lifespan.
Steve Auckland New Zealand
Further Reading:
Why do larger animals live longer than smaller ones? WonderQuest
Life Span of Ancient Man — long or short? WonderQuest
Gastrotrich, Wikipedia
Giant tortoise, Wikipedia
Life span, Encyclopedia Britannica
Tuararas, University of Michigan's Animal Diversity Web Q: Which mammal has longest and which the shortest life span?
A: If we just look at mammals, then primates are the longest lived group and man is the longest
lived of the primates: 122 years (Jeanne Louise Calment, 1875 - 1997). Tiny shrews live the
shortest: maybe 1 to 1.5 years. Interesting enough, among primates the bigger your brain, the
longer you live. The faster you live, though, the shorter you live. Squirrel-like rodents live two
or three times longer than mouse-like rodents because their rate of metabolism is slower.
(Answered April 4, 2001)
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