PurpleHeart wrote:A couple points of interest here, the first being scientific.
http://en.wikipedia.org/wiki/Haldane%27s_ruleThis is called Haldane's Rule. This was discovered many years ago and is scientific evidence "not to pair" two different species.
What do you mean by this last sentence? If I interpret your grammar correctly, in reading it as "This is scientific evidence that you shouldn't do so", then I must point out that science does no such thing. Science, in and of itself, is with a method of acquiring knowledge. Prescriptive and descriptive laws are inherently different, and science deals with the discovery of the latter. There is no "should" in science, except insofar as it can help us predict the consequences of our actions. It does not go on to tell us whether the consequences are desirable, and so whether we should perform the actions.
Haldane's Rule, as cited in the article, is "When in the offspring of two different animal races one sex is absent, rare, or sterile, that sex is the heterozygous (heterogametic) sex". What this law
does tell us is that
if different animals breed, and
if they produce offspring at all, it is more likely to be inviable (in some fashion) if they are of the heterozygous sex. It doesn't say anything about how viable hybrids tend to be -- it only talks about
what usually goes wrong
when something goes wrong.
Hybrids in general are, of course, less viable than monospecific offspring. The reason for this is that the gene pool of a species tends to conform to a set of mutually of compatible genes -- any genes that are likely to result in offspring that aren't viable, will be weeded out from that gene pool. Two distinct gene pools, as seen in hybrids, do not operate under these evolutionary constraints -- they will thus be fairly similar (or they couldn't hybridise), but not quite that similar (they lack that selective pressure towards conformity). As with mutations, then, hybridisation will lead to deviations from normal genetic traits.
As is often pointed out in the case of mutations, the vast majority of deviations from normal genetic traits are deleterious, if only for the reason that (as Richard Dawkins likes to say) there are many more ways of being dead than being alive; mutations are undirected, but precisely because they are random, most of them are bad. Some will be good. So it is with hybrids. Hybrids may very well be spectacularly successful, but just as with mutants, this is after natural selection weeds out -- kills -- the unsuccessful majority.
From this we may draw the conclusion that a hybrid pairing is
more likely to produce non-viable offspring than an intraspecific pairing (excepting perhaps -- I speculate -- in cases where the species gene pool is so small as to make the dangers of inbreeding even greater). This is a quantitative statement, of course, and I lack the data to say by
how much.
Whether you then think it is a good idea depends on what you are trying to do and what odds or chances you are willing to take. For the
ethical aspect, it may be well to consider that these are sensitive and intelligent animals, quite capable of suffering.
Responsible husbandry tells us not to do this. We have all this evidence that says the results will not be something you will like or be kind to their off spring. Then to go further and say these are two TINY Macaws, and historically only the larger ones have managed to put together any type of DNA chain to wit a baby that might survive.
I'm not sure what this last sentence means ("only the larger ones have managed to put together any type of DNA chain to wit a baby that might survive"), but I'm intrigued. Can you clarify? What's this about macaw DNA? Do you know of any studies? (I don't mean to sound challenging -- if you do, I'd like to read them!)
As a breeder we know they do NOT FALL IN LOVE, this is a human emotion and not yet relegated to our birds. This is purely hormonal in their action.
Of course it's hormonal, but that's something they have in
common with humans, not a differentiating factor. What do you think love is?
