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Asked by to Thon, Catherine, James, Natalie, Shaylon on 16 Jun 2014. This question was also asked by .
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Shaylon Stolk answered on 16 Jun 2014:
We think Bowhead Whales, a kind of plankton-eating whale, can live to be up to 200 years old. Other whales can live into their 90s. One orca in Washington State in the United States is estimated to be about 111 years old.
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James Bell answered on 16 Jun 2014:
Good question, there’s still some debate about this (partly because we don’t know the lifespans for a lot of mammals or other animals) but as far as I know, big whales (baleen whales – the ones that filter out tiny shrimp from seawater for their food) are among the longest living mammals. The oldest Bowhead whale is thought to have been around 211 years old when it died (but it was probably between 177 to 245 years old – depends which method you use to calculate the age)
Some mammals can live a very long time but other animals can live way longer. Some coral species can live for thousands of years (especially in the deep sea when animals grow much slower normally).
It’s worth noting probably that we don’t know very much about lifespans of animals because they often don’t live to their maximum age in the wild (usually because of disease or being eaten by other animals). Human lifespans are quite extended these days, because of all the advancements in technology and medicine and the fact that we have no predators. Further back in human history when we didn’t live in houses like now (only a few thousand years ago), our lifespans were probably much less (for prehistoric humans, a 50 year old person would be really pretty old, I’m sure many of you have grandparents who are much older than that now but still very healthy).
Generally, an animal’s lifespan is fairly closely linked to its lifestyle and how quickly it grows. Lots of deep sea species grow very slowly and they might be as much as 40 years old before they are even mature adults (can reproduce). Dogs and cats by comparison grow much quicker, and will be mature after 2-3 years, but don’t often live to be older than around 16-17 years old. One of the reasons big animals like elephants or whales can live so long is probably to do with the fact that once they are fully grown they have no natural predators, because they are too big.
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Catherine Offord answered on 16 Jun 2014:
Shaylon and James have answered this one pretty thoroughly – but I think it’s interesting also to compare animal lifespans to other organisms as well.
The oldest living plant is thought to be a pine tree in North America. You can estimate the age of a tree by studying the number of rings in the trunk. The ring count of this tree gives an age of five THOUSAND and sixty three years old! We animals don’t even come close.
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Anthony Caravaggi answered on 17 Jun 2014:
My fellow scientists have covered a lot of the common ground here, so I’ll just throw out a few more thoughts on long-lived organisms.
The oldest plant in the world might be(!) the North American pine Catherine mentioned. But then again, it may not. There is an aspen tree which reproduces clonally, that is, it creates exact copies of itself. These clones all stay connected to each other by means of an underground root system. Scientists think that this colony may be 75,000 – 80,000 years old! Now if they’re all exactly the same and they’re always connected, does that mean they are the same plant or separate plants? Botanists – plant scientists – have argued about this for quite a while. I tend to think of them as the same plant.
Tuataras, reptiles native to New Zealand, and one of a handful of animals considered ‘living fossils’ may live for up to 200 years. The giant tortoises of the Galapagos islands may live even longer!
Some animals may not even have a maximum life span. Many flatworms are thought to be potentially immortal due to the way they grow and heal. There is also a type of jellyfish which might be immortal due to the way it regenerates cells. But I’m not specialist, this is James’ area.
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James commented on :
I have heard of these jellyfish Anthony – the way I understand that it works (and I’m not really an expert here either as I study things that live on the seabed and jellyfish spend most of their lives floating in the water column) but the jellyfish in question (Turritopsis dohrnii) is thought to be functionally immortal because it can revert to a ‘younger’ life stage as part of it’s normal life. This kind of hits a reset button in their cells.
What normally happens in cells is that as they age they can get damaged and start functioning badly or wrong, they are then usually destroyed by the body (or not – which is one of the ways animals can get cancer). In this amazing jellyfish however, this cell-reset feature seems to overcome this ageing process.
We think of this jellyfish as immortal in the sense that there’s no theoretical maximum lifespan it could have but in real life it almost certainly gets eaten or dies because of disease – I guess it’s like the elves in Tolkein’s Middle Earth – they can only die if something kills them 😛
Thanks Anthony – I’d forgotten about the jellyfish!!