Fewer chromosome doesnt mean less genes or genetic material, it just means the chromosome are all joined up together. Species with more chromosomes have smaller chromosomes.

Yes, in fact there are plenty of species which have differing numbers of chromosomes within that species. All different chromosome numbers mean (if everything else is the same) is that there is slightly higher chance of genetic abnormalities and the offspring is slightly higher likelihood of being infertile.

Species is just an arbitrary classification. Interbreeding is only one factor used to determine what is a species. Its thought that only female neanderthal human hybrids were fertile and not males, so that one justification for considering us seperate species. Just how likely an offspring is to be fertile could also be taken into account. If two species have to breed a million times to produce 1 fertile offspring, it doesnt mean the two are the same species, there is never going to be considerable gene flow between those two groups.

Chromosome number is just one measure of compatibility and its not a particularly good one. Some species have wildly different chromosome numbers within the same species and yet breed fine. Plenty of pairs of species with the same number of chromosomes can't breed.

All you can really say is that chromosomal number differences and rearrangements tends to reduce the fitness of offspring and reduces the likelihood of fertile offspring.

Taking the pill or pregnancy or anything else has no impact on the rate at which your body processes and kills off eggs. They are constantly recruited and start developing, but are only ovulated if the hormone balance is right. Otherwise they are just reabsorbed by the body.

Can you name some examples?

What on earth does the length of a giraffes neck have to do with instincts?

> Important- The canine behavior you talked about is not learned and is inborn.

Source? Ive seen dogs raised alone do the head shaking thing. I don't buy that its a learned behaviour and not instinct.

>For example, why do some types of cancer account for the majority of cases while others are rare?

Different cancers are not simply different mutations. The same mutation can cause different cancers and the same cancer can be caused by different mutations. Rare cancers tend to be those in tissues/organs that have little cell division, so there is less opportunity for mutations to arise and spread.

Any source for that being the reason for potatoes having more genes?

Venoms are mostly proteins, so yes of course they can be a target of antibodies. Antibodies recognise fairly short fragments of proteins, not an entire virus or bacteria.

Also venoms are biological, and I don't think purely chemical means anything, everything is chemical

Microorganisms actually within your body itself (not the GIT, lungs, skin etc) are always eliminated (well at least attempted to). On the other hand the immune system on the skin and mucous membranes are far more tolerant of microbes, a full immune response will not be triggered by the presence of microbes. Exactly how the immune system moderates the microbes at these sites is a pretty big topic.

The stuff on Indians mixing with Aboriginal Australians is interesting, the stuff on dingos doesnt seem at all conclusive though, wonder what other dingo researchers would say on those points. Seems more likely that the dingo came from Indonesia/PNG.

This is the extent of the evidence on dingos in that paper btw

>However, the dingo also first appears in the fossil record at this time and must have come from outside Australia (46). Although dingo mtDNA appears to have a SE Asian origin (47), morphologically, the dingo most closely resembles Indian dogs (46).

Genetics trumps morphology every time. Morphologically dingos are more similar to Tasmanian tigers than anything else on Australia, but origin wise that means nothing at all.

Some developed a poison by chance, and that trait was selected for, as it made predators less likely to eat them.

Stomach acid doesnt break down many (possibly most) of the toxins that bacteria and mould produce, which can already be at high concentrations in contaminated food. So whether or not the bug survives or not doesnt help you.

Bacteria that cause gastrointestinal infections have various ways to survive digestion. Salmonella for example relies on being consumed at the same time as food and being digested in high numbers, when you eat a meal, the food offsets the pH of your stomach, making it closer to neutral. Other bacteria have specific protective mechanisms against stomach acid.

Also stomach acid isnt all that acidic, you would know when you throw up your tongue doesnt dissolve away or anything, its not equivalent o the acid used in acid attacks for example.

Doesn't sound right, do you have a source? Most early symptoms (especially those OP mentioned) are related to the immune response and the immune response could be triggered before the virus even enters cells, or more likely sometime after when the virus has replicated to high enough levels to trigger a sufficient response. In any case, it certainly should take days for the first viral particle to enter and replicate for the very first time.