weird question coming your way....?

Question

i was thinking the other day, how come when a black cow and a white cow have a baby...the little cow has black and white patches, but when a human couple of one black and one white have a child, the baby is a shade of both parents??

Answer 1

Genetic inheritence in cows and humans is not the same. But the main reason is that you are looking at apples and oranges - on a cow you are looking at "hair", and for the humans you are looking at "skin". Let me ask you this - what is the color of the skin under a black and white cow?



Animals have genes that make different colored haid, but it appears that humans do not that gene. It was probably lost (made inactive) a long time ago. Why don't apes have hair patterns like cows?



Again, it appears that humans do not hve the genes to allow the display of different color hair.



Ron.

Answer 2

I do not know about cows' heredity, nor whether there are alleles for patches even in single-colour cows. If there are, this would explain it. If all the patches were coloured white, the cow would be all white, but offspring could still be particoloured.



This certainly happens with cats. An all-black cat still has tabby alleles, and (in certain lights) you can see slightly different shades of black, arranged in tabby stripes.



With people it's different. All races are self-coloured. Skin colour, like hair-colour or eye colour is controlled by genes.



Now imagine (it's more complicated. but this will do for a start) that only one gene controls skin colour. A mixed-race couple (pure black, pure white) reproduce. Since black is dominant and white recessive, the white gene will not influence the colour; it is dominated by the black, and all offspring are pure black.



If these offspring now reproduce with other interracial people, all those having a black gene (from either father or mother) will be black, regardless of the other gene. Those who get WW (the same from both parents) will be white.



In fact there is a range of genes influencing skin colour. In each pair, black (we really ought to say, dark brown, since the blend as we shall see is not grey but a lighter brown) is dominant. In a 2nd generation pairing not all of these pairs in a given coupling will have a B gene: some will contribute WW to lighten the mix. Hence the range of skin colours in children of the same couple.



It is possible, then, for a mixed-race couple to produce children ranging from dead black to dead white, though these extremes are rare. And to further complicate things, there is probably no such thing as a pure black or pure white person: even a blonde from Finland probably has some melanin (black skin colouring) producing genes, and even a black, black African might have a few white genes. Hence some degree of mixing occurs even in the first generation, though the children of these unions tend to be on the dark side.



Something of the same sort also happens with hair and eye colour.

Answer 3

I don't think crossing black and white cows will yield a patchy cow for the same reason crossing a black and white dog won't give you a Dalmatian. Patchy fur is just as distinct as white and black are. Every black patch on the cow's fur represents a single cell in the developing embryo that received a signal to produce black fur. As the embryo grew that cell divided over and over again and each cell that came from that original cell will produce black fur. Geneticists sometimes refer to these as clones. The signal that makes these clones is what is unique to the patchy cows. Black cows and white cows do not receive this signal as embryos.

This is a very simplified answer and may not be how it actually happens in cows, but generally this is a common theme used during development.

Answer 4

If you put a full pure bred black cow to a full pure bred white cow which has only that colour in its genes then as black is generally a more dominant colour then the calf would be either black or white and not patchy but more than likely black. i think this is a real silly question it is obvious that one of the cows has patchy cow in its family history and as we humans tend not to be patchy we will be a bit of both but if genes are dominant then we will look more of the colour that the dominant gene parent is.

Answer 5

I think it's because with cows, the genes for fur color are co-dominant, which means both are shown. But in humans, genes for skin color is incomplete dominance, which means it is a mix between the two. This is a guess based on what I learned in Biology class. Hope I'm right, lol.

Answer 6

"selractrad" is the only one who came close to answering your actual question.



Yeah, it's not unknown for bi-racial children to be spotted; it's only rare.



Cows and other domestically bred animals have spots because one day long ago, when the first spotted cow was born, human beings decided it was a desireable trait, and chose that animal for selective breeding. Thus, it is now common.



Spotted humans are not considered particularly attractive by other humans -- or, it will suffice to say that members of the opposite gender will not line up out the door to form an instant harem of the necessary reproductive and economic resources necessary to increase the spotted characteristic in the population.



The first blue-eyed blonde was a different story, I guess ;)

Answer 7

Both skin and fur colours are determined by a lot of genes. Human skin colour is determined by 3 genes, with 4 alleles each, the more alleles, the darker the skin colour. The in-between shade is more commonly presented, due only to probability.

Hope this helps!

Answer 8

The correct derivation of the cow fur is the amplitude of the recombination, and the dominant allele, for instance, if the cow is black, then the fur is black, but if the allele is a spoted cow, then it becomes a spotted cow.

Answer 9

That is a very good question. Allow me to answer.

The easy word to use is genetic co-dominance. Humans always express both genes for the hair/skin color they inherit. This is why we always come out "blended".



In cows, the process of expressing hair/skin color is different. The two genes for black and whit are not expressed with equal strength in each cell. Only one color gene is turned "on" (i.e., being used) in each hair follicle, thus we never see any gray cows.

Answer 10

Wow hmmm



There will be someone out there smarter than me able to answer this question.



However, thinking about it in a logical way I would guess that it has something to do with how the Chromosones gel during gestation.



With a human the X and Y chromosones mix together and they contain all the information (race, hair colour and so on) and the most dominant come out on top. I would imagine, although I don't know, that in cattle the chromosone set up is different and that brings itself out in a mixed way.



Hmmm I shall ponder further. Brilliant question though thank you

Answer 11

so u think ppl should have spots?



well several different reasons, we dont have the same genetic makeup as cows, bout 92% i'd guess.



For humans there are no races, only pseudo races. You could take two ppl who were opposite in every characterisitc imagineable and they'd still have 99.999999% the same genetic makeup.

Answer 12

It is not unknown for a mixed-race child to have patches of different coloured skin. (Unusual, but not unknown).

It is all to do with genetics, which gene is dominant and which is not. Your cow example does not allways work, either.

Answer 13

because arent almost ALL cows black and white there fore they have a black and white cow i have never seen an all white cow and an all black cow

Answer 14

its because the laws of inheritence are different for cows and humans

Answer 15

good question but wouldnt the baby look silly with black and white patches

Answer 16

well humans can't grow great big spots all over them like cows.

can you imagine a white baby with great big black spots all over it lol.

Answer 17

well maybe becuase humans are different to cows! i think you have too much spare time on your hands!

Answer 18

because people aren't cows.

Answer 19

mmm Never thought of it like that. Good question though.

Answer 20

thats a good question lol

Answer 21

i dont know "MOO"

Answer 22

idk but r u serious