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Post by Exalt on Jan 17, 2024 4:37:02 GMT 5
Why are female mammals usually the smaller of the two, and why might the exceptions occur?
Additionally, how might sexual dimorphism occur?
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Post by Supercommunist on Jan 17, 2024 7:46:16 GMT 5
Why are female mammals usually the smaller of the two, and why might the exceptions occur? Mammals tend to take care of their young and the females almost always are the ones that serve as caretaker. Taking care of babies means more mouths to feed so being smaller decreases the amount of calories she needs. Males, on the other hand, tend to fight or compete for reproduction so getting bigger to a certain point is advantageous. King cobras are a good example of the parental effect. Female snakes tend to be larger than males, but king cobras are exception, most likely because female cobras actually defend their nests unlike most other snakes. Male jacanas who function as the sole caretakers are smaller, weaker, and less aggressive than the polyandrous females. If it offers an advantage it will likely manifest. Female invertebrates tend to be bigger because bigger = more eggs, and unlike mammals don't usually feed their young. A big reason why bird of prey likely exhibit dimorphism is to broaden their range of prey. Mothers take larger prey while the fathers take smaller prey. |
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Post by Exalt on Jan 17, 2024 8:42:25 GMT 5
I appreciate the King Cobra example: one time I was asking a friend for what distinguishes them from the Naja cobras. Speaking of which, it has forever stuck with me that the King's genus is Ophiophagus. Literally, "snake-eater." Oddly enough, I saw some Jacana parenting in planet earth III the other day. (called a lily-trotter there.) The adult females were not shown or mentioned.
Any ideas on why hyenas or leopard seals ended up with larger females?
(The reason I actually mentioned mammals in the first place was because I wasn't sure of how this applies to other groups. They are also the ones most known for live-birth, which I thought might affect things.)
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Post by Supercommunist on Jan 17, 2024 9:39:44 GMT 5
I am not sure why female spotted hyenas are larger but given the interest in the subject there might be some strong hypothesis out there. As for leopard seals, it's possible that they're adaptations for eating krill solves the "extra mouths" problem. I've noticed many species of filter feeding whales have larger female than males. According to various studies filter feeding is very energy efficent. I saw some theories online that whale calves benefit from having a larger mother since they would have a higher chance of raising their offspring which they produce only once every two or three years. www.nbcnews.com/id/wbna29187881 |
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Post by Exalt on Jan 17, 2024 23:46:44 GMT 5
It seems debated on whether Cygnus Falconeri could fly or not. Any opinions?
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Post by Exalt on Jan 23, 2024 4:36:23 GMT 5
Why did birds lose their teeth?
Unlike with most of these, I did manage to find a little on the subject: one idea was that you are reducing the weight to a degree, another was that it allows them to spend less time in the egg.
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Post by Infinity Blade on Jan 23, 2024 5:10:36 GMT 5
Why did birds lose their teeth? Unlike with most of these, I did manage to find a little on the subject: one idea was that you are reducing the weight to a degree, another was that it allows them to spend less time in the egg. Those ideas do make sense, since a head without teeth is a lighter one, and not developing teeth means less nutrients/energy required to develop them. But the primary reason was likely to allow for the consumption of specific food items, namely seeds. Having a hard beak seems to have been the bird lineage's way of adapting to a granivorous diet. This might, in fact, be a reason why edentulous birds survived the K-Pg extinction. www.sciencedirect.com/science/article/pii/S0960982216302494 |
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Post by Exalt on Jan 23, 2024 21:45:18 GMT 5
How would T.rex, or a similarly built species, get up off of the ground? And if they couldn't, how might they have slept?
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Post by Infinity Blade on Jan 24, 2024 3:42:55 GMT 5
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Post by Exalt on Jan 25, 2024 3:54:16 GMT 5
Another question, and this might veer a bit too much into psychology, but regardless: Why might Spiders and Snakes be the most common animals humans are afraid of? I've heard of the hypothesis of snakes and primates influencing each other, but otherwise, it's worth pondering, I feel.
EDIT: I remembered one that has bugged me for ages.
Years ago, I read that the Hercules Beetle is the strongest animal in the world, relative to body size: back then it was supposedly 850 times, which even at the time I wanted proof of, as this would mean that it could carry some humans. Nowadays it seems the number is viewed as around 100 times.
Have there been any demonstrations of it, or other rhino beetles, doing some impressive lifting? I'd be a bit concerned about such tests as you could plausibly hurt the creature in the process, but nonetheless.
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Post by Supercommunist on Jan 25, 2024 9:50:01 GMT 5
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Post by Exalt on Jan 28, 2024 22:04:08 GMT 5
So I watched a video earlier that discussed the idea that if Megalodon is indeed longer than previously thought, it would have been more efficient at traveling for longer distances. Since Megalodon is apparently viewed as not very fast, is it plausible that it was exhausting some of the prey it hunted?
Either way, I'd like to know ideas on how it went about this regardless of body plan.
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Post by Infinity Blade on Jan 29, 2024 7:12:55 GMT 5
So I watched a video earlier that discussed the idea that if Megalodon is indeed longer than previously thought, it would have been more efficient at traveling for longer distances. Since Megalodon is apparently viewed as not very fast, is it plausible that it was exhausting some of the prey it hunted? Either way, I'd like to know ideas on how it went about this regardless of body plan. So putting aside whether or not the study will hold up in the future (I already know from some on Twitter that there is previous/upcoming research that seems to contradict some of the stuff it claims), traveling for longer distances could just be referring to cruising speed (that is, the "normal", casual speed you'd expect to see it moving at by default, just like our walking speed). Previous research suggested that megalodon had a high cruising speed for a shark, which already seems conducive to traveling longer distances (without a need for an elongated body). In any case, I don't think it was exhausting its prey. I don't think any shark practices that hunting strategy, so I don't suppose megalodon did either. Just a fast burst of speed via ambush probably would have been sufficient. |
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Post by Exalt on Jan 29, 2024 8:10:27 GMT 5
I see. I had started to feel that the idea was foolish at some point after suggesting it.
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Post by Exalt on Jan 31, 2024 4:15:57 GMT 5
I've got a couple more.
1. Why did African Homotherium go extinct? Without the details it doesn't seem to make sense. Why couldn't they make it when Lions and Hyenas managed to?
2. Why are amphibians the only metamorphosing vertebrates?
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