400-year-old Greenland shark ‘longest-living vertebrate’ (2016) • Hacker News Board

Re: 400-year-old Greenland shark ‘longest-living vertebrate’ (2016)

#61

Post by dnhz » Sat, Mar 27, 2021, 11:47 PM UTC

grawprog wrote: post #11

fastball wrote: post #3

Confirmation bias is a creepy thing sometimes. I was literally asking my Google Home last night what the longest living vertebrate was and it told me the Greenland shark. Had a whole conversation about it over dinner, arguing about how accurate we think these age-establishing methods are. Though the more interesting part of our conversation (I would say) was wondering how ages work out in practice. For example why do…

Heartrate has been found to play a big part. https://pubmed.ncbi.nlm.nih.gov/9316546/ Animals with slower heart rates tend to be longer lived. An interesting sidenote are bats, which have heart rates about the same as similarly sized small mammals like mice, but due to their nightly torpor state where their heart rate is significantly lowered, they tend to live 20-25 years opposed to the 3-4 mice usually live.

Birds are metabolically much more active than mammals yet many have long lifespans. This prompted another finding that the number of cortical neurons can explain a large part of the variation in lifespan across species.

https://www.labroots.com/trending/cell-and-molecular-biology...

Re: 400-year-old Greenland shark ‘longest-living vertebrate’ (2016)

#62

Post by sandworm101 » Sat, Mar 27, 2021, 11:56 PM UTC

danmaz74 wrote: post #7

2OEH8eoCRo0 wrote: post #2

> The team looked at 28 sharks, most of which had died after being caught in fishing nets as by-catch. Nice job- the shark had done just fine for ~400 years.

Of the shark was by-catch it means that it had been caught by commercial fishing and had already died when the scientists examined it.

Bycatch is not always dead. Google around for the recent case of a whale caught in a japanese net for weeks. They eventually took action to drown it as "bycatch" and chop it up for meat rather than let it go.

Re: 400-year-old Greenland shark ‘longest-living vertebrate’ (2016)

#63

Post by staticassertion » Sun, Mar 28, 2021, 12:05 AM UTC

poochdog wrote: post #31

fguerraz wrote: post #15

What startles me is how much we've changed their environment in that single individual's lifetime. That shark was the equivalent of a human teenager when the industrial revolution started.

Delusions of grandeur notwithstanding, not much it seems.

There are plastic bags at the bottom of the mariana trench, arguably the most remote places on the planet with regards to human exploration.

It's hard to imagine a piece of the world that we haven't had an impact on.

Re: 400-year-old Greenland shark ‘longest-living vertebrate’ (2016)

#64

Post by jonplackett » Sun, Mar 28, 2021, 12:09 AM UTC

2OEH8eoCRo0 wrote: post #2

> The team looked at 28 sharks, most of which had died after being caught in fishing nets as by-catch. Nice job- the shark had done just fine for ~400 years.

Was just thinking this. The tragedy of this is completely missed in the tone of the article, as if this is just some fun new thing we learned about sharks.

Re: 400-year-old Greenland shark ‘longest-living vertebrate’ (2016)

#65

Post by fabioyy » Sun, Mar 28, 2021, 12:22 AM UTC

and we killed

Re: 400-year-old Greenland shark ‘longest-living vertebrate’ (2016)

#66

Post by yesenadam » Sun, Mar 28, 2021, 12:48 AM UTC

rubicon33 wrote: post #17

grawprog wrote: post #11

Earlier quoted context omitted.

Heartrate has been found to play a big part. https://pubmed.ncbi.nlm.nih.gov/9316546/ Animals with slower heart rates tend to be longer lived. An interesting sidenote are bats, which have heart rates about the same as similarly sized small mammals like mice, but due to their nightly torpor state where their heart rate is significantly lowered, they tend to live 20-25 years opposed to the 3-4 mice usually live.

Assuming this is true, I recommend everyone start running! If I am regularly running, my resting heart rate at night drops into the upper 30s. During the day sitting down, 45-50. If I haven't been running (for a week or longer) it picks back up in to the mid 40s at night, and around 60 for normal sitting.

(Assuming you're not joking) You don't seem to be counting all the extra times your heart beats when you're actually running.

Re: 400-year-old Greenland shark ‘longest-living vertebrate’ (2016)

#67

Post by chihuahua » Sun, Mar 28, 2021, 12:50 AM UTC

aloer wrote: post #42

2OEH8eoCRo0 wrote: post #2

> The team looked at 28 sharks, most of which had died after being caught in fishing nets as by-catch. Nice job- the shark had done just fine for ~400 years.

Related: there’s a new documentary on Netflix called Seaspiracy It has some staggering numbers regarding the amount of by-catch caught every day

My first paid job was an internship at a research institute where I had to examine buckets of bycatch and count how many of various species had been caught. I think it was from shrimp fishing and the bycatch was just small fish (1 to 6 inches).

For some fish, we would figure out their age by looking at some tiny bone pieces under a microscope and counting rings, similar to tree rings.

I have no idea how I ended up in that job, I have no interest in fish or fishing or the ocean.

Re: 400-year-old Greenland shark ‘longest-living vertebrate’ (2016)

#68

Post by jagger27 » Sun, Mar 28, 2021, 1:13 AM UTC

46756e wrote: post #34

Isinlor wrote: post #21

Earlier quoted context omitted.

By far the most important reason dictating lifespan is evolvability - the ability to adapt genetically [0]. This has so great effect that it's easy to observe even in a simple computer simulations. If you don't adapt and the environment is changing, then you go extinct. Think about this sharks and how much their environment has changed since they were born. As a spices they will have a very hard time adapting to the…

I’m not educated on this topic at all, but wouldn’t birth rate be more relevant than aging? If this shark lives 400 years but has kids often, it could also go through 900 generations like the mice. Presumably if the environment isn’t favorable then the old members of the species would die off anyway.

Consider that a litter of sharks born in year 100 would be very closely related to a litter sharks born in year 400. Imagine the same pair of sharks mate over that span of time, those siblings are even closer. To me, evolution is a very deep graph of descendants. The scenario you propose is a very wide and shallow graph.

N.B.: I'm a layman on this topic as well.

Re: 400-year-old Greenland shark ‘longest-living vertebrate’ (2016)

#69

Post by Zenst » Sun, Mar 28, 2021, 1:21 AM UTC

IgorPartola wrote: post #50

aloer wrote: post #42

Earlier quoted context omitted.

Related: there’s a new documentary on Netflix called Seaspiracy It has some staggering numbers regarding the amount of by-catch caught every day

I saw the preview for this last night and on the one hand I want to watch it because I feel that it’s important to know this stuff, but on the other hand I really just want to bury my head in the sand. Over the past year I’ve realized just how much we are killing the planet and how powerless I am so do anything at all about it and it’s depressing me every time I think about it and not in a figurative sense.

You are not powerless - ethical buying, if everybody did that then things would change as companies run on money, so vote with your wallet. Effort to research and may find in some area's it's down to picking the best of a bad choice, but little by little mindsets are changing and you do have the power.

Business runs on money - vote with your wallet as that is your power, use it, don't loose it.

Re: 400-year-old Greenland shark ‘longest-living vertebrate’ (2016)

#70

Post by IgorPartola » Sun, Mar 28, 2021, 1:39 AM UTC

Zenst wrote: post #69

IgorPartola wrote: post #50

Earlier quoted context omitted.

I saw the preview for this last night and on the one hand I want to watch it because I feel that it’s important to know this stuff, but on the other hand I really just want to bury my head in the sand. Over the past year I’ve realized just how much we are killing the planet and how powerless I am so do anything at all about it and it’s depressing me every time I think about it and not in a figurative sense.

You are not powerless - ethical buying, if everybody did that then things would change as companies run on money, so vote with your wallet. Effort to research and may find in some area's it's down to picking the best of a bad choice, but little by little mindsets are changing and you do have the power. Business runs on money - vote with your wallet as that is your power, use it, don't loose it.

That’s a nice thought and I’ve tried that before but the “if everybody did that” is the key. I can bend over backwards to only buy local organic food just to have the farm driven out of business by a Walmart Super Center and watch as a new mega container ship, new mega mall, new mega church gets built. I don’t think I spend nearly enough money on retail stuff that would actually tip the scales or even make anyone notice that I stopped shopping at the “unethical” stores.