Questions related to mammals.
3
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1answer
74 views
Why do sloths come down from the trees to defecate?
I'm under the impression that most sloths exhibit this behavior, but why? They are slow moving and so have no way of escaping from predators when on the ground. Not to mention the energy they expire ...
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0answers
40 views
Can mammals from different species reproduce?
I'm curious on how genetically different can two animals be in order to reproduce. Could they belong to different species?
One example is the mule which is the offspring of a donkey and a horse, in ...
3
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2answers
53 views
Do dolphins really sleep?
I have always wondered, if dolphins sleep with one eye opened, do they really sleep at all?
According to this article dolphins indeed shut down their brains.
I already googled it. No help from ...
0
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1answer
51 views
Are ape communities more “anarchist” or “communist” in structure?
I am using these terms because we can imagine them quite good, I guess ;)
By "anarchist" I mean that the ape wants to live without the rule of others apes(same biological race or other) and he pursue ...
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0answers
11 views
How compatible are mammal digestive systems?
I'm interested in what kinds of nutrients mammal digestive systems extract from food and would like to know how similar are the outputs of these systems.
For example, if it is possible to ...
3
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0answers
145 views
Can a person really die quickly from biting their tongue?
A common trope in certain circles (like Eastern martial fiction), is someone committing quick suicide by biting his or her tongue. But is this really possible?
The internet turns up millions of ...
2
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1answer
26 views
How do bats distinguish between day and night?
How do bats distinguish between day and night? Do they hunt at night - if yes, how they know that?
Are they afraid of sunlight?
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0answers
31 views
Are there any mammals in which polyspermy produces viable zygotes?
Are there any mammals in which polyspermy produces viable zygotes? In the wikipedia page it is mentioned that there is a delicate equilibrium between female defenses against many sperms, which ...
1
vote
2answers
78 views
Do any cells change in size or mass as mammals grow?
That is to say, are there cells that, between infancy and adulthood, get larger? Or is all growth done entirely via cell division? I'm wondering if it is safe to assume that the approximate number ...
10
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1answer
163 views
Could a fetus properly develop in micro/zero-gravity?
I suppose another way of looking at the question is: how important is gravity for the development of mammal fetuses?
And if things would go wrong, what sort of things would they be, and what would be ...
4
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1answer
65 views
Birds from the Family Columbidae Feed Young “Crop Milk”
Birds from the family Columbidae (e.g., doves and pigeons) produce a fatty, milk-like substance in their crop. The secretion is often referred to as "crop milk." They feed crop milk to their young ...
7
votes
1answer
59 views
What hair do aquatic mammals have?
I'm reading an essay on the creating of the Mammalia zoological classification (Londa Schiebinger, The American Historical Review, Vol. 98, No. 2 (Apr., 1993), pp. 382-411).
It contains the statement ...
5
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1answer
70 views
What selective factors drove the evolution of lactose in lactation?
As far as I can determine, lactose, and the monosaccharide galactose have few biological uses outside of mammalian lactation. It not only required enzymes for its production, but enzymes in offspring ...
6
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2answers
86 views
Do omnivore mammals vary food preferences based on dietary needs?
I'm wandering if mammals that can eat many different kinds of food (omnivores) vary their preference for food not only based on the availability, but also based on dietary needs?
I'm looking at this ...
6
votes
1answer
495 views
Why can't humans drink sea water?
Why can't humans drink sea water?
It would seem to be a huge evolutionary advantage for an animal to be able to drink sea water rather than have to rely on fresh water, and it's provably not ...
5
votes
1answer
574 views
Do other male mammals except for humans have nipples?
When I grew rabbits, I had a pair, one male and one female. And while the female's nipples were quite prominent, especially after giving birth, I don't remember the male having any nipples at all.
Do ...
5
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1answer
92 views
Why was polyploidy not lethal in certain octodontid rodents?
As discussed in Why is polyploidy lethal for some organisms while for others is not?, polyploidy is normally lethal in mammals.
However, two species of Octodontidae (South American rodents), are ...
5
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2answers
60 views
laboratory mice, nutrition, and humans
It seems that many nutrition experiments [directed at human diet] are carried on laboratory mice. Is there any justification that nutrition that is good or bad for laboratory mice will also be same ...
