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Telomere shortening rate predicts species life span

pnas.org

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Re: Telomere shortening rate predicts species life span

#51

Post by twjdeboer »

pawelmurias wrote: post #42
mysterypie wrote: post #37

Earlier quoted context omitted.

> this makes me think that telomeres are not the main cause of aging-related death That's an interesting argument, but couldn't you use the same reasoning to argue that telomeres are the main cause of aging-related death? The mental model I'm thinking is: As you run out of telomeres, you get diseases and you can't reproduce - and that’s maladaptive. So there’s evolutionary pressure to slow down the shortening rate, u…

If you lived longer still you might father more children.

Yes, but because of increased risk of disease and lower physical ability, you would also be a larger strain on your group/family. I think we should see this more as a survival of offspring and less as fathering more offspring.

Re: Telomere shortening rate predicts species life span

#52

Post by hvidgaard »

mrfusion wrote: post #40
function_seven wrote: post #19

Earlier quoted context omitted.

Okay, you shamed me into doing it :) So, this is really rough napkin math, but here goes: Assuming that... ... a sedentary person (Donald) has a resting BPM of 80. ... an active runner (Justin) has a resting BPM of 60, and a peak BPM of 180 (while running) If Justin runs for a solid 2 hours, five times a week, he will have 158*60*60 + 10*60*180 = 676,800 beats per week While Donald, who doesn't run, but averages 1 ho…

Thanks for doing the math. I’d say 130-140 would be better than 180 for someone in shape. Most people can’t even hit 180 after their 20s.

It depends on your goals. If you just want to do the 5K as fast as possible, you'll be close to your max heart rate (180). If you're just "leisure" running (aka. you can talk while running) I suppose 140 is reasonable.

Re: Telomere shortening rate predicts species life span

#53

Post by martindbp »

collyw wrote: post #45
tomp wrote: post #44

Earlier quoted context omitted.

Average isn't that relevant. It's driven down by early childhood deaths & childbirth deaths (but after a point - menopause - childbirth deaths end).

Infectious disease killed many before old age. Antibiotics are a pretty recent invention.

And infectious disease was probably a much smaller problem for hunter gatherers living in small groups, which has been the case for the vast majority of our evolutionary history.

Re: Telomere shortening rate predicts species life span

#54

Post by kuprel »

pawelmurias wrote: post #42
mysterypie wrote: post #37

Earlier quoted context omitted.

> this makes me think that telomeres are not the main cause of aging-related death That's an interesting argument, but couldn't you use the same reasoning to argue that telomeres are the main cause of aging-related death? The mental model I'm thinking is: As you run out of telomeres, you get diseases and you can't reproduce - and that’s maladaptive. So there’s evolutionary pressure to slow down the shortening rate, u…

If you lived longer still you might father more children.

There's probably pressure for species to not have longer lifespans. Youthful thinking and fresh perspectives are important. Wise old perspectives can get deeply ingrained and can't be changed easily. The free market for example experiences similar phenomenon where a new startup will outcompete a big old corporation. An industry that moves quicker (tech) evolves faster than one that doesn't (healthcare).

Re: Telomere shortening rate predicts species life span

#55

Post by dahart »

jayd16 wrote: post #28
jes5199 wrote: post #15

this makes me think that telomeres are not the main cause of aging-related death. My mental model is: if you run out of telomere before you get old, you start to get disease - and that’s maladaptive. So there’s evolutionary pressure to slow down your shortening rate, up to a point. Once it becomes unlikely that you’ll outlive your telomeres, there’s no more pressure. So your telomere length + rate becomes a measureme…

This doesn't really make sense does it? There's only really evolutionary pressure up to the end of your child rearing years, no?

> There’s only really evolutionary pressure up to the end of your child rearing years, no?

No, at least according to some anthropologists and evolutionary biologists. For example see the Grandmother Hypothesis https://en.m.wikipedia.org/wiki/Grandmother_hypothesis

Re: Telomere shortening rate predicts species life span

#56

Post by tensor »

kuprel wrote: post #54
pawelmurias wrote: post #42

Earlier quoted context omitted.

If you lived longer still you might father more children.

There's probably pressure for species to not have longer lifespans. Youthful thinking and fresh perspectives are important. Wise old perspectives can get deeply ingrained and can't be changed easily. The free market for example experiences similar phenomenon where a new startup will outcompete a big old corporation. An industry that moves quicker (tech) evolves faster than one that doesn't (healthcare).

The evidence doesn't support what you imply: that older people can't learn or come up with novel ideas. Fresh perspectives are important, but there are more ways than ignorance (e.g. youth) to find them. For example, cross domain work often yields amazing new results; it's a great way to bring in fresh perspectives.

Re: Telomere shortening rate predicts species life span

#57

Post by isostatic »

Tade0 wrote: post #50
tomp wrote: post #47

Earlier quoted context omitted.

Yeah, but the impact isn't that great. According to Our World In Data [1] a 20-year-old would expect to live to 60 in 1850 (before penicillin), versus to 80 now. [1] https://ourworldindata.org/life-expectancy#it-is-not-only-ab...

That's still long enough for a person to see their grandchildren reach and cross puberty.

Especially in a world where kids were born when the parent was in late teens or early 20s, rather than now when average age is 28 and pushing higher.

This means first grandchildren in early 40s (rather than late 50s), and first great grandchildren by mid 60s (rather than mid 80s)

Re: Telomere shortening rate predicts species life span

#58

Post by beowulfey »

pawelmurias wrote: post #42
mysterypie wrote: post #37

Earlier quoted context omitted.

> this makes me think that telomeres are not the main cause of aging-related death That's an interesting argument, but couldn't you use the same reasoning to argue that telomeres are the main cause of aging-related death? The mental model I'm thinking is: As you run out of telomeres, you get diseases and you can't reproduce - and that’s maladaptive. So there’s evolutionary pressure to slow down the shortening rate, u…

If you lived longer still you might father more children.

In evolutionary terms you become a competitor with your male offspring for reproduction, which may hinder natural variation.

Re: Telomere shortening rate predicts species life span

#59

Post by reallydude »

tomp wrote: post #44
collyw wrote: post #38

Earlier quoted context omitted.

Human's average lifespans have been a lot shorter throughout history.

Average isn't that relevant. It's driven down by early childhood deaths & childbirth deaths (but after a point - menopause - childbirth deaths end).

Historical average is relevant. I have an 18 year old cat. It's an aberration. We evolved under specific pressures. Only recently, have we removed specific age gates.

Re: Telomere shortening rate predicts species life span

#60

Post by pfd1986 »

axaxs wrote: post #9
PhilWright wrote: post #5

The total number of heartbeats also predicts lifespan, although apparently not as accurately. So is the heartbeat total just a coincident or still a factor somehow?

I've seen this before and get the gist, but at face value, it's ridiculous. A human who runs every day may expend twice the heartbeats of a sedentary person. He or she will not live half as long, or anything close to it.

I believe the argume is valid for order of magnitude calculations (see Geoffrey West YouTube videos, for an explanation).

+-20 years wouldn't make a difference in a log plot

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