Linked Questions

-1 votes
1 answer
131 views

Why don't women continue to produce ova indefinitely?

Why has the human body not evolved to produce more ova? Is there some technical reason that makes is easy while the fetus is developing, but much harder later in life? Or, perhaps more likely, is it ...
Iris's user avatar
  • 19
-1 votes
0 answers
8 views

Why some receptors have such high activation ceilings? [duplicate]

Why does the brain have receptors that have such a high activation celling, that no endogenous neurotransmitter could even come close to fully activate? Which ultimately results in there being certain ...
Antony Theo.'s user avatar
0 votes
0 answers
17 views

What prevented invertebrates from discovering flight a second time? [duplicate]

Vertebrates evolved powered flight three times in history, being pterosaurs, birds, and finally, bats. Invertebrates were the first to evolve flight on the planet... but flying insects remained the ...
Darth Biomech's user avatar
10 votes
1 answer
1k views

Why are venomous mammals and birds so rare in comparison to reptiles and fish? [closed]

Why are venomous mammals and birds so rare in comparison to reptiles and fish? Metabolic reasons? Morphology? Selection pressures? Why are not all reptiles venomous but many are? Why are platypuses ...
li tchi.'s user avatar
  • 129
1 vote
0 answers
63 views

Reasons behind the sticky substances are used by poplar in buds

It is well known that sticky poplar buds falling on a car can seriously damage the paint. Also these scales from poplar stick to the paws and fur of animals like Velcro. Personally I don’t think the ...
Mikhail Gaichenkov's user avatar
0 votes
0 answers
24 views

How long does it take for a creature to adapt for a different diet?

For the sake of the question, let's say that a population of piscivorous birds are put in a Europe-sized box. Half of the box is sea, populated with their diet of fish and crabs and cephalopods, and ...
Craig Morrison's user avatar
0 votes
0 answers
26 views

Visibility of a spiders web from a distance

Given that the diameter of a spiders web is, for instance, far smaller than a thread of cotton. Why are spiders' webs so visible from a distance? What property of spiders' webs makes them so obvious (...
3-14159265358979323846264's user avatar
3 votes
0 answers
36 views

Why electrical synapses are more common in invertebrates?

I suppose it's because they live in an environment where there's a constant vulnerability to predators and they need to respond quickly. But it's not really the case for many invertebrates and besides ...
Venkatesh Choudhary's user avatar
1 vote
2 answers
701 views

Why does 360 degree rotation not seemed to ever have evolved?

Of the designs of species that have evolved, I am curious why a 360 degree rotation, like a joint that can spin, does not seem to have evolved, for example wheels or a propeller. Like, is there some ...
Julius Hamilton's user avatar
1 vote
0 answers
83 views

Why Sexual Reproduction instead of Gene Transfer?

So, as I understand it, the prominent theories for the evolution of sex are that it increased variation allowing for faster adaptation in evolutionary arms races, and that it gets rid of deleterious ...
Thomas Anton's user avatar
1 vote
0 answers
57 views

Confused About Why Red Queen Hypothesis Wouldn't Apply to Deer's Color Vision [duplicate]

In this site,https://www.livescience.com/why-are-tigers-orange, it says ""But there seems to be no evolutionary pressure, particularly for deer, which are the main prey of the tiger, to ...
MeltedStatementRecognizing's user avatar
2 votes
0 answers
248 views

Have lions, tigers, and cheetahs begun to lose or not yet fully gained tree climbing traits?

Leopards, jaguars, and the domestic cat all regularly climb trees, but lions and tigers rarely do. From what I can tell from a basic online search, the latter are inexpert tree climbers, but they ...
user avatar
2 votes
2 answers
172 views

Why do cells use microRNA to break down mRNA, instead of not transcribing it in the first place?

As I understand it, microRNAs are used to ensure that certain genes are only expressed when needed. The way this apparently works is that when the translation products of an mRNA are not required the ...
Sam's user avatar
  • 29
0 votes
0 answers
59 views

Why DNA polymerases don't have helicase activity

RNA polymerases have intrinsic helicase ability, while DNA polymerases don't. I am curious why DNA polymerases evolved in such a way that they lack the ability to unwind DNA.
Son of Sevenless's user avatar
0 votes
0 answers
48 views

What is evolutionary advantage of Spirogyra to be multicell?

Spirogyra is just a set of cells connected to each other; it has no leaves, roots, etc... It even doesn't have multiple layers of cells like Hydra. So what is evolutionary advantage for Spirogyra ...
Vitalii's user avatar
  • 101

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