This is the DETAILED reply I got from AIG
To answer your first few questions, in short the answer is that God created several original kinds of each animal and these speciated (mostly after the Flood) where they have lost and are still losing genetic variation when they speciate. For more information on this please see the following articles:
http://www.answersingenesis.org/articles/aid/v3/n1/zonkeys-ligers-wholphins
http://www.answersingenesis.org/articles/am/v3/n4/bara-what
We don't answer eschatological questions, so I can't answer your "bedbug in the millennium" question. Please see the following for more info:
http://www.answersingenesis.org/articles/2009/10/19/where-do-we-draw-the-line
Regarding you questions about insects being on the Ark, the short answer is “probably” they were taken on board the Ark. There was no requirement in God’s command to take representatives of all the different animals that would have mandated taking insects on the ark (but there was no prohibition either). Insects are defined separately in the Hebrew language. For instance:
1) All the animals taken into the Ark are described as basar, “flesh”. This term (when used of whole living animals rather than simply the animal body) is never used of invertebrate animals.
2) “the life (nephesh “soul”) of all flesh is the blood of it” (Lev. 17:11, 14; Deut. 12:23; Gen. 9:4). In the Biblical and everyday sense, invertebrates do not have blood (Heb. dam).
3) Basar is qualified by the phrase “asher bo ruach chayyim”, “which has in it the spirit of lives” (Gen. 6:17; Gen. 7:22). This additional phrase is likewise never used of invertebrates.
4) In Genesis 7:14 kol ha’oph (every flier) is defined (through apposition) as kol tsippor kol kanaph (every bird every wing i.e. every bird of every sort). The phrase tsippor kanaph definitely excludes insects.
Thus only the following groups were required on the basis of the Hebrew text to be taken into the Ark: (1) all birds, (2) all land-dwelling reptiles and mammals, (3) possibly some of the more terrestrial amphibians, or possibly all amphibians.
Of course we know that Noah could have taken insects onto the Ark, if God brought them to him, and it would have been practically impossible to keep insects from joining the crew of the Ark. Most probably then, there were a number of types of insect on the Ark. They wouldn’t have been prevented by God either, in fact, since God commanded Noah to bring plants on board the Ark (Gen. 6:21) and many insects are pollinators, it seems at least some types were necessary. For example, ants help plant health by clearing the detritus (dead organic matter) that might otherwise clutter and choke out light and certain nutrients. They also produce waste that is essential as fertilizer for many plants. Bees would have been almost mandatory as pollinators (and of course as a bonus, would have been the source of honey).
Some insects also are quite capable of surviving on the flotsam and other debris caused by the catastrophic effects of the Flood. There was quite possibly huge masses of floating vegetation all over the earth at the time of the Flood. Insects can survive long periods without food by going dormant, as well. Since Scripture doesn’t explicitly state one way or the other, we cannot be dogmatic.
Given the delicate nature of some insects (butterflies, moths and dragonflies for example) it seems almost necessary to include them on the passenger list of Ark animals, and this may indeed be one of the criteria. If the adult stage of an insect could not survive on flotsam in heavy rain and ocean spray conditions, or if the larval stage of an insect was terrestrial, or did not have the ability to go into dormancy if aquatic, or if they were required as pollinators or plant "caretakers", it seems likely that God would have had Noah take them aboard. Other insects could have survived in aquatic larval stages or on floating mats of vegetation or flotsam. This is just a working “model” though, and I am not tied to it that strongly, but it does accord with the fact that God did want to preserve some of every "kind" of life through the Flood.
It is an interesting hypothesis by some creationist scientists that if God may have delayed some animals starting a strictly carnivorous diet until after exiting the Ark, when there would have been enough carrion from the Flood washed up onto land or fish in tidal or remnant pools to support the rather small population of carnivores post-Flood. Most carnivores are carrion-eaters, or temporarily modify/supplement their diet with carrion. This would have allowed Noah to feed most animals with vegetation rather than meat, and would also have provided the herbivores a chance to avoid immediate predation and establish a larger population before being preyed upon. We must also trust the fact that God’s will was for the remaining animals to repopulate the earth. Other creation scientists have also postulated a Divine-induced hibernation or torpor like state in many Ark animals which would have minimized the amount of food needed by each animal. Others have suggested that the few true carnivores on board were sustained with an insect diet during the Flood. Many carnivorous animals are at least partly insectivorous, and some actually will switch to an insect diet when meat is scarce. Insects therefore may have been the bulk of the carnivore diet on board the Ark.
There is no scriptural problem with insects being on board, and they would provide an ergonomic, economic and labor-easy way to provide meat to the carnivorous animals. Ants may have been necessary in large quantities for aardvarks and anteaters. (One radical explanation is that carnivores were fed with rodents, who in a year's time if brought on board pregnant can produce hundreds of thousands of offspring from a single population.) I should also point out that Gen. 6:21 records God telling Noah "And you shall take for yourself of all food that is eaten, and you shall gather it to yourself; and it shall be food for you and for them."; there is nothing in this statement that precludes Noah from taking dried meat, insects, dried fish or live animals on board to feed the carnivores. So again, insects may have been a necessity on board the Ark.
I should also point out that the RSV and the ESV of Genesis 7:21 use the phrase EVERY SWARMING THINGS THAT SWARMS UPON THE EARTH; (every other translation uses the phrase creeping thing), and this could refer to insects as well as amphibians and lizards.
