Live data from Hacker News

Mammals Evolved into Ant Eaters 12 Times Since Dinosaur Age, Study Finds

news.njit.edu

31–40 of 52 posts

Re: Mammals Evolved into Ant Eaters 12 Times Since Dinosaur Age, Study Finds

#31
post #2

The weight of all ants on Earth is roughly equal to the weight of all humans- aka there are a lot of ants. And can be found everywhere mammals are able to live. So they make sense as a food source

You mean "i.e." I believe

Re: Mammals Evolved into Ant Eaters 12 Times Since Dinosaur Age, Study Finds

#33

Earlier quoted context omitted.

[flagged]

wow, was that a misplaced and unnecessary barb. srsly, granted I didn't add a ton of value to the thread, but if a simple gesture of gratitude for a needed moment of human levity results in downvotes and attempts at judgy put-downs, something's wrong here. please look at my comment history before deciding who belongs on what forum. I love this place and will accept whatever further karma hits come for mentioning karm…

I think it is just tradition (as on many sites) to downvote comments about karma. Telling you to go to reddit was rude though.

Re: Mammals Evolved into Ant Eaters 12 Times Since Dinosaur Age, Study Finds

#34

Earlier quoted context omitted.

I was thinking maybe that's why the evolved stingers, but it turns out ants evolved from stinging wasps not vice versa.

Your username makes me think you'd be a good person to ask: Sorry, what? (Edit, this sounds like I don't believe you, but it is more that I am in disbelief!) Ants evolved from stinging wasps? Were they flying at that time? Or were wasps at some point non-flying and the 'wasps' grouping is a wide one like 'beetles' is? This is such a fascinating space I know very little about.

Yes, ants evolved from wasps, and it's really not that surprising if you take a close look at a typical ant and a typical wasp, pretty much the only difference are wings and coloring. There also exist wingless wasps, and some of them are black and really quite indistinguishable from ants by non-entomologist. And that's after over 100 million years since the ants diverged from the wasps! Talk about a successful evolutionary design. Your closest relative from 100 million years ago was a little vaguely rat-like thing. (Edit to answer your specific question: the ancestor of ants and wasps obviously was winged and flying, since both families still have at least some winged members).

As a sibling has already pointed out ants do fly during "nuptial flight", and then discard their wings... wings would only be a hindrance for their largely underground lifestyle. Also ants have retained the stinger which also functions as an ovipositor (egg layer), and some species still use it for defense and pack a wallop of a poison, right up there with some of the of the worst wasps. Google "bullet ant" for some good stuff. Other ants just bite, and the burning you feel is from their saliva which consists mostly of an acid named after ants: fourmic acid (ant is "formica" in latin).

Edit to add one more random factoid that will surprise a lot of people: termites are not related to ants at all, and they evolved from... (drumroll)... cockroaches! It's rather harder to see the resemblance, except for their diet... both are capable of digesting (with help from endosymbiotic microbes) pure cellulose. And while termites don't really resemble ants either, parallel evolution has chosen the same strategy of retaining the wings for the fertile individuals who go on a nuptial flight and then discard their wings and try to found new colonies.

Re: Mammals Evolved into Ant Eaters 12 Times Since Dinosaur Age, Study Finds

#35

how many times things evolved into sharks? ichtiozaur, dolphin/orca anything else?

I guess we’ll see if they have the endurance. Sharks have been around for a while after all. But, Orca have surpassed sharks in terms of badassery, right? And it isn’t that close. They aren’t evolving into sharks, they are the upgrade!

Re: Mammals Evolved into Ant Eaters 12 Times Since Dinosaur Age, Study Finds

#36
post #2

The weight of all ants on Earth is roughly equal to the weight of all humans- aka there are a lot of ants. And can be found everywhere mammals are able to live. So they make sense as a food source

While comparing things... a colony of leaf-cutter ants (which form some of the largest colonies with as many as 2 million individuals when the colony is mature) has roughly the same metabolic rate as cow (easily measured from the CO2 at the exits of their nest). So don't think of ants as tiny animals, think of ant colonies as fairly large animals.

Re: Mammals Evolved into Ant Eaters 12 Times Since Dinosaur Age, Study Finds

#37

how many times things evolved into sharks? ichtiozaur, dolphin/orca anything else?

The mosasaurs also developed a caudal fin (vertical, like sharks and ichthyosaurs, not horizontal like whales and dolphins) and eventually they became quite shark-like, though not as fish-like as ichthyosaurs.

Between ichthyosaurs (who evolved in Triassic) and mosasaurs (who evolved in Cretaceous) there existed also a group of marine crocodiles (Metriorhynchidae; who evolved in Jurassic), which also had caudal fins and were quite shark-like.

So there have been at least 4 groups of amniotes that looked like sharks, cetaceans among mammals and at least 3 groups of diapsids.

However all these marine predators looked like sharks from the point of view of locomotion, but none of them had the kind of teeth specialized for cutting that are characteristic for sharks. Teeth resembling those of sharks are found only among some other fish, e.g. piranhas, whose bodies do not resemble sharks.

Re: Mammals Evolved into Ant Eaters 12 Times Since Dinosaur Age, Study Finds

#40

how many times things evolved into sharks? ichtiozaur, dolphin/orca anything else?

Beyond ichthyosaurs and cetaceans, carcharhinification (shark-like convergent evolution) also occurred in plesiosaurs, mosasaurs, certain teleost fish like barracuda, and even the extinct thalattosuchian crocodylomorphs.

Jurassic-Cretaceous marine crocodiles (like also ichthyosaurs and mosasaurs) looked like sharks, i.e. they depended mostly on their caudal fin for swimming.

On the other hand, there was no resemblance between sharks and plesiosaurs or pliosaurs. The latter swimmed using their lateral fins, somewhat like marine turtles and penguins, not like sharks. Also the dentition of plesiosaurs and pliosaurs had no similarity to sharks, so except for being big predators there were no resemblances between them.

Post reply on HN