Interestingly, Sharks became a thing around the same time that massive fungi structures that looked like trees existed.
So there could be planets where mushroom forests are dominant like one might see in the science fiction televisual dramas.
Honestly, I disagree. It is much more surprising to me that lifeforms I recognize are older than stars. They're different timescales in my mind that I never even considered comparing.
That's way back. What else was around in the oceans back then? Bony fish? Crabs? My octobuddies?
And they're gonna go away because some wingnut convinced a bunch of people that their fins cause boners.
That's not even 0.1% of the total fish we kill every year. Granted, that's just sheer numbers, not weight
Sharks hunt smaller predatory fish, which hunt for the same fish as humans. By killing sharks the fishermen are actually increasing their competition.
And meanwhile there have been 108 attacks on humans in 2022
https://www.floridamuseum.ufl.edu/shark-attacks/yearly-worldwide-summary/
Commercial fishing is literally the worst thing in the world, in my opinion, and that's just one fun example of why
A family member once had to resort to traditional chinese medicine so solve an issue - and it acctually worked, I will admit upfront - but I kept hearing how shark cartilage capsules was the best to reinforce joints and one day I just snapped and replied along the lines of "by that same logic, to obtain insulin we should be grinding pig pancreas into pills for insulin".
we used to use cow pancreas to get insulin actually. fortunately bioreactors exist and some clever people figured out how to gmo bacteria to make insulin
Is a species being poached to extinction? If so, it's probably because there's some sort of fertility/virility "medicine" derived from it that Asian men will pay insane money for. -tiger -rhino -civet -pangolon -shark
And then you add the fact that sharks have barely evolved because they've been the perfect silent killer since the dawn of time.
Another fun fact:
Sharks don't make sound. They don't have any organ for the purpose of making sound. That is creepy as all hell.
That can't be true. I distinctly remember the shark in Jaws: The Revenge roaring. So get your facts straight.
Just because they didn't change their appearance doesnt mean they did not evolve. It is somewhat misleading to say that, but conveys a point I guess.
More relevantly, the fossil records for sharks are mostly their teeth and jaws, because all their other bones are cartilage and rarely fossilize.
"Sharks haven't significantly evolved in appearance in 350 million years" is therefore based on reconstructions made under the assumption that the old sharks mostly looked like current sharks, which may or may not be true.
Though we can get a surprising amount of information that way, for example one change is that their jaws used be more at the end of their snout instead of more underslung like today, like so:
You'll note the Goblin Shark still has hints of that design.
I made sure to say barely instead of not at all, but you're right, there was certainly some evolution happening
Yeah, thankfully Megalodon isn't cruising around anymore. Though that might have delayed European expansion until they had metal clad vessels....
That sounds like a fun story, like a Pride and Prejudice and Zombies but instead it's Master and Commander and Megalodon.
You can't prove the non existence, but you can be very sure about some things. Megalodon lived near the surface, because it liked warm water(AFAIK), so it's likely that if it wouldn't be extinct there's a high chance that we would notice it, since Megalodon was kinda big.
Yeah okay, seems plausible then. It's more fun to believe otherwise though, not gonna lie. After all, there's still so much we don't know about our oceans.
Yes, actually. Example: Triglidae
They are bottom-dwelling fish, living down to 200 m (660 ft), although they can be found in much shallower water. Most species are around 30 to 40 cm (12 to 16 in) in length. They have an unusually solid skull, and many species also possess armored plates on their bodies. Another distinctive feature is the presence of a "drumming muscle" that makes sounds by beating against the swim bladder
It is partly true. Polaris is in fact a triple star system. The youngest of the three stars (Polaris Aa) is indeed younger than sharks at between 45 and 67My old. It is in tight orbit with Polaris Ab which is 500My old, and Polaris B which is 1.5By old and a little bit farther away. Here’s a pic from Hubble:
https://en.m.wikipedia.org/wiki/File:Polaris_alpha_ursae_minoris.jpg
This cannot be true.
Oh. https://www.smithsonianmag.com/smart-news/respect-sharks-are-older-than-trees-3818/
This should not be true.
I think it’s also worth mentioning that Polaris Aa, the youngest star in the triplet, is also the brightest by 3 orders of magnitude. Without Polaris Aa, we wouldn’t actually consider it as the North Star at all…so I think you are safe to continue using this as a fact.
Go blow some people’s minds, everyone!
Fun fact: the morning Star (first star we see in the morning) is in fact also the evening star (first Star we see in the evening). It's also not a star; it's just Venus.
I want to know how three stars can form as a system at very different times. Shouldn't they have similar ages?
My understanding is that, on a cosmic scale, these timeframes are not tremendously different!
Technically just one of the three stars (the big one). The other two are 500 million and 1.5 billion years old.
Shark facts aside, the fact that Polaris is a ternary system, rather than a single star has completely blown my mind.
My grandfather, in the army in the 1950s, mentioned that there was an eyesight test by having cadets look at a star and ask them how many light points they saw.
I'm not convinced it was Polaris and its partners, there might have been another star system used as the test. I learned about Polaris being a triple star system years later.
If anyone knows what star systems would had been used as an eye test... I imagine it's something that could be within our eyes limits.
Unlikely Polaris. The luminosity difference between Polaris Aa and the other two is 3 orders of magnitude. Mizar and Alcor (the doublet second from the end of the Big Dipper) has been used for centuries as a vision test. If you can see the doublet, it’s equivalent to 20/20 (or 6/6) on an eye chart.
Seriously! Thank you for confirming!
I did a bit more research and found this link outlining how they have been used as eye tests for a long time! Fascinating!
I found a source saying he's mistaken. If you scroll way down, it says all three stars are 70 million years old.
https://ui.adsabs.harvard.edu/abs/2021ASPC..529...72N/abstract is my source for the ages but if there's newer data please enlighten me!
People forget that life on earth has been around for an extremely long time. We believe that single cellular life first appeared around 3.5 billion years ago. We also believe that the universe is around 13.8 billion years old. That means life has been around and evolving for around 25% of the time the universe has existed. Life operates on a scale far beyond our comprehension.
Another fun fact about life. We think that multicellular life only appeared around 600 million to 1.2 billion years ago. So life was probably single cellular for billions of years. The complexity of life has rapidly increased since then and will continue to do so.
Edit: new research suggests that complex multicellular life may have appeared around 2.4 billion years ago.
Even if humans manage to kill off most life on Earth it will continue to exist, propagate, and become more complex. Again we’re talking about billions of years. There have been huge shifts in climate and mass extinctions many times before and yet here we are.
Yeah I think most people don't know or comprehend that there have already been like 5 mass extinctions in our planets lifespan. It's going to take something like getting hit by 4 gamma ray bursts at the same time to completely wipe life off of planet earth.
true, we're just gonna be like a soft reset button, like a windows reinstall without formatting, where it just shoves everything into windows.old
True, it would be difficult to completely turn Earth into a lifeless rock, but I think humans are up to the task.
There are plenty of things we can't kill and, in fact, live on things we might use to kill them. Extremophiles that live in environments nothing else can. Bacteria that live off gamma radiation. We would have to dedicate ourselves to ridding all life on purpose to kill everything. We would have to live long enough to be the last things to kill if that was the goal.
Eh I doubt it. Every single nuke ever built combined still doesn't come close to the power of the Chicxulub asteroid (the one that killed the dinosaurs) and even that impact didn't come close to eliminating all life on Earth. Unless someone accidentally compresses a mountain into an artifical black hole or something there probably is no way to wipe out all life on Earth.
Mars was once habitable but lost it's magnetic field, wiping it's atmosphere. Venus was once habitable but taken over by a runaway greenhouse effect.
I'm not saying they ever had life or that we're going to suffer the same fate, but it's definitely possible to wipe a planet clean.
75% of all species, not all life. Larger species and photosynthesizers were more heavily affected, while smaller species, scavengers, and deep sea life were less affected.
And I'm not a biologist, but I'm pretty sure even 75% of all life, not species, still wouldn't be close to completely ending life on Earth, cause in the end as long as some microbes survived around a hydrothermal vent somewhere total extinction would be avoided.
I still think that "lifeless rock" does not specify how lifeless - theoretically extinct or just lifeless enough to make human life either extinct or just miserable. I took it as the latter, and in that case even lesser cases than 75% of all species would suffice.
The first case, the theoretical and non-human focused pov is quite another thing. Like you said, there's so many opportunities and adaptations for life to seap through the combs of doom :)
