
By
Madeleine Kando
Another year has ended and we are all excited about it. We made new year’s resolutions which we probably won’t keep and we convince ourselves that the new year will be better than the last. But the real reason for all this frenzy is to celebrate the fact that the Grim Reaper hasn’t come knocking at our door.
But what’s so special about a year? Why not a day? A month? A century? Doesn’t that reek of anthropocentrism? There is no line drawn across the universe that says: “Today is January 1 2023.”
Some insect species never live long enough to celebrate New Year. They don’t even make it to the next day. The female mayfly ‘Dolonia Americana’ only lives for a few minutes as an adult. Can you imagine having to do your entire life’s business in under 5 minutes? Learn to fly, find a mate, make babies and then lay eggs in a safe spot? You wouldn’t have time to eat or go to the bathroom (which is just as well, since mayflies don’t have a mouth). You wouldn’t have time to retire and write your memoirs. You couldn’t wish anyone Happy New Year! You could wish your buddies Happy New Minute, but even that would not fit in your busy schedule.
Ordinary house flies are given some wriggle room, but they too have to cramp their entire lives into a few weeks. No wonder they are so determined to land on that sugar cube, no matter how many times you try to squash them. *
Mammals are somewhat better off, but some still have to sprint through their lives before their time is up. The lowly mouse lives only 18 months and a shrew lives for only about a year. Their metabolic rate is too high to allow them to live much longer. On the other hand, bowhead whales, the longest living mammal on earth, can live over 200 years.
Amazingly, some animals grow extremely old, because they have what is called ‘negligible senescence’. Senescence is the condition or process of deterioration with age, which means that once an animal grows old enough, it stop growing old. An example of negligible senescence is the Greenland shark. Covered with battle scars, it can live up to 500 years. Similarly, the 500 year old Ming clam could have gone on living its incredibly long life, were it not for a bunch of marine biologists who fished him out of the ocean and froze him on board to take him to the lab. Of course he instantly died.
In the plant kingdom life spans begin to increase dramatically. The Pando tree, one of the oldest organisms on Earth, is 14,000 years old. It is really a colony of clones of an original tree, but all of the trees are connected through an underground network of roots. In this way, aspens continue to live long after a single tree may fall or die.
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