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1500 questions
19
votes
5 answers
Has there ever been an attempt to create nutritionally tailored food for adult human consumption?
For all domestic animals, and for all animals kept in laboratory, complete and precise composition of perfect food is figured out (cat food, dog food, cattle, rats, laboratory monkeys and apes) -- which contains precise composition of carbs, fats,…
Andrei
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19
votes
2 answers
What are the major evolutionary pressures for Bioluminescence?
What are the major evolutionary pressures for Bioluminescence?
Aleksandr Levchuk
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19
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2 answers
Possible? When a pregnant woman suffers an organ damage, fetus would send stem cells to the damage organ to help repair it?
I am quite sure that there is this blood-placental barrier between the mother and the baby so that nothing (except a type of antibody) can pass through it.
But I remember reading somewhere that when a pregnant woman suffers an organ damage, fetus…
user661
19
votes
5 answers
Origin, or source, of rhesus negative in human blood
This is my first post here, so please be gentle. I recently learned that I have Rh- blood (I'm A-), and was idly looking into blood types on Wikipedia. I was surprised to find that relatively few (~15% of all) humans have it, and most of those seem…
Patrick87
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19
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2 answers
Why do we assume that the first humans were dark-skinned?
According to the article Dark skin and blue eyes: How Europeans once looked:
It is widely accepted that Man's oldest common forefather was dark
skinned, and that people became more pale as they moved further north
out of Africa into colder…
anomal
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19
votes
1 answer
Haidinger's brush: Is this a by-product of the eye's physics, or are there any evolutionary grounds for it?
The human eye is, very subtly, sensitive to the polarization of light. This is an effect known as Haidinger's brush (see Wikipedia article of this name).
What, if anything, is known or at least intelligently speculated about the evolutionary…
Selene Routley
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19
votes
1 answer
Crossbreeding mouse and chinchilla
The MGI Mouse Genome Informatics website states for the Mus musculus 129 strain, popular in biomedical research, that:
Origin: Dunn 1928 from crosses of coat colour stocks from English fanciers and a chinchilla stock from Castle.
Source
However,…
teunbrand
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19
votes
3 answers
Is atmospheric nitrogen chemically necessary for life?
It is my (very basic) understanding that neither plants nor animals utilize the nitrogen in the atmosphere. Humans do not make use of atmospheric nitrogen through respiration and plants do not extract nitrogen from the air, but rather from the…
Wyck
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19
votes
1 answer
How do porcupines keep from pricking each other while mating?
How do porcupines keep from pricking each other while mating? It seems like they would constantly be scratching each other.
J. Musser
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19
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5 answers
Introductory biology text for an outsider
I'm a maths major and I have an interest in learning biology. I know very, very little; I know how babies are made and that's about it. Could anyone recommend a stimulating text to read for its own sake and also to use to learn biology?
Kieran Cooney
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19
votes
1 answer
What would cause red-haired people to become fewer?
There is this misconception that red-haired people are going to die out. This person on the Internet ("howstuffworks") also connected it to a marketing campaign of a hair dyer company. But I'm interested in a specific citation that he gives in that…
akraf
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19
votes
1 answer
Is this a hornet?
I live on the 2nd floor of an old apartment building in Vancouver BC (Canada). A couple of years ago we had an issue with a hornets nest that was difficult to remove because of its location. They managed to find a way into the actual apartment…
Simon
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18
votes
2 answers
Why are organs not harvested from deceased cancer patients?
From my understanding, cancer is not contagious, and if a cancerous cell from a patient is introduced to a healthy person, then the immune system of the latter can destroy this cell. In such a case, why are internal organs from cancer patients not…
Harvey
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18
votes
4 answers
What is the evolutionary reason behind the fragility of teeth?
Almost all organs in the human body have a rather large threshold within which the organ or tissue is capable of repairing itself using materials supplied by the body, whether it's made from organic tissue or structural proteins. Wounds and minor…
Sir Quill
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18
votes
2 answers
Why is there now only one Salmonella species?
Once upon a time, I chanced upon an old microbiology book that detailed the rather colorful world of enterobacteria. Salmonella in particular stood out, as it seemed there were a lot of species: typhi / typhosa, paratyphi, gallinarum, typhimurium,…
user132