It seems you answered the question-- reproduction (i.e. population increase) and resources. Also many animals will split up into clans. The elder and/or strongest lead the groups.
For the animals that do migrate in an organized way, the migration is unlikely to be very far. Even large mammals are limited by geographical features like desert, mountains, and oceans.
But most animals do not have organized migrations.
Here is my answer. What is 2^30? Over 10,000,000. Point being that populations should spread quickly--exponetially minus the death rate. You wouldn't expect them to stay in Turkey.
Exponential growth usually isnÃ¢â‚¬â„¢t seen in larger animals like lizards unless the conditions are exceptionally good. But if they did reproduce fast, itÃ¢â‚¬â„¢s true that they might leave Turkey. But to get all the way to North America, South America, Australia, and all of the islands in between within 4000 years? That doesnÃ¢â‚¬â„¢t seem very plausible to me.
This is a weakness of evolution theory. The populations of vertebrates in 500 million years should have overrun the land many times, extinguishing resources and causing mass death many times over.
There are several mass extinctions in the old earth timeline, and some could have been due to a problem with resources. However, animal populations are often controlled by predator-prey relationships. If a population of herbivores begins to grow and eat all of the plants, the carnivore population will have more prey and grow as well. When the carnivore numbers become too high, the herbivore population will decrease in size. The plants will have a chance to grow again, and the whole cycle will start over. This is being observed in ecosystems all the time, and thereÃ¢â‚¬â„¢s no reason why it couldnÃ¢â‚¬â„¢t have happened in the past as well.
Genes are either turned off or on. Even in us. There are 'housekeeping' genes, and genes that are activated as the need arises.
ItÃ¢â‚¬â„¢s not always so black and white. In many cases a dimmer switch is a better analogy than a light switch. Genes can be turned to high, low, or anywhere in between.
Can you give me some data on these 'suppressed' genes? I mean i fully expect that if we have the same kind of hair then there are going to be similar genes. But the suppression is what I'm inquiring into.
Hair is made of the protein keratin, as you probably know. There are different types of keratins, and different genes coding for each type. Transcription factors can bind to the promoter sequences of these genes and increase the amount of keratin produced. Conversely, transcription of these genes can also be suppressed. If transcription factors are absent, then transcription will not be initiated and the protein will not be produced. Suppression can also occur if the promoter sequence is blocked. HOXC13 is a transcription factor which is involved in human hair growth. The amount of HOXC13 present and itÃ¢â‚¬â„¢s affinity for the promoter sequence affect the amount of hair keratins produced. Human are also missing a keratin gene that is present in chimps, which explains some of the differences between their hair and ours.
Isabella, I'm disappointed in you . Canidae is a family, not a species. In this case there could been a kind or several kinds of dogs that could interbreed on the ark.
Oops, I should have clarified what I meant by dogs. I wasnÃ¢â‚¬â„¢t referring to Canidae, but rather to the domestic dog (Canis lupus). I just wanted to illustrate the physical variation that evolution (in this case, by artificial selection) can produce within a single species.
Let's be fair though. Bariminology is a much younger field, it has much less personel and funding. Much of the research must be done by biologists or microbiologists on their own time--unless they are working for a non for profit creationist organization like AiG.
What does baraminology research involve, exactly? IÃ¢â‚¬â„¢ve looked for information about it in the past, but IÃ¢â‚¬â„¢ve found nothing. You say itÃ¢â‚¬â„¢s a young field, but even if it were properly funded where do you see it going? WeÃ¢â‚¬â„¢ve already analyzed animal genotypes and deduced their relations to one another. ThatÃ¢â‚¬â„¢s how we define a species: two organisms that have enough genetic similarity to reproduce. And by using genetics, physical morphology, and developmental biology, we can take the relationship even further and classify similar animals according to genus and family and so forth. But all of this has been done already. What is baraminology looking for? Some sort of imaginary wall within the continuous spectrum of genotypes, so that you can conclusively say that two animals are separate kinds?