Difference between revisions of "Kangaroo"

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Kangaroos are the largest Marsupials alive today. They are now native to the continent of Australia. There are four sub-kinds in the kangaroo baramin -- the Western Grey Kangaroo, the Eastern Grey Kangaroo, the Red Kangaroo, and the Antilopine Kangaroo -- or at least sixty-nine species according to evolutionary views^[1], which include wallabies and tree-kangaroos.

Description

Kangaroos have large ears on top of their small heads, a long snout, and short arms with clawed fingers. Their legs are strong and powerful, good for leaping. Their feet have four toes at the end of elongated metatarsi that they rest on when standing. They also have a powerful, thick tail that is used as support when standing, a third-leg when walking slowly, and for counterbalance while leaping. Like all Marsupials, female kangaroos have a pouch on their stomachs in which they carry their young.

Diet

Kangaroos are herbivores, eating grass, roots, and shrubs. They have a chambered stomach similar to sheep and cattle. They are able to regurgitate their food, chew it again as cud, and then swallow it for digestion.

Social Order

Kangaroos travel in mobs of about ten or more males and females. The leader of the mob, called a "boomer", is a male determined by age and size. The boomer has access to females in his mob for mating and will wander around the mob intimidating any other males who try to mate with his harem.

Reproduction

Male kangaroos will go around the mob checking the females’ cloaca. Many times, males are rejected by the females because of size if they are small. In other cases, if a larger male is checking a female out, she may just move away. Sometimes, when a male is checking out a female, the female will urinate for the male, who will sniff the urine. Some studies show that this ritual is for the male to see if the female kangaroo is receptive to him or not.

If the female is responsive to the male, she raises her tail and the male will follow her. Sometimes the kangaroos will scratch each other’s tails or the male will give the female a back rub before mating. When the female is ready to mate she will arch her tail.

Female kangaroos usually only have one baby kangaroo (called a "joey") at a time. The newborn joey weigh as little as .03 ounces when first born, after which it crawls into its mothers pouch where it will nurse, grow, and develop. They spend a lot of time in their mothers pouch developing. The Red Kangaroo joey will stay in their mothers pouch for about eight months and Grey Kangaroo joeys stay in there for about a year.

Development of the Young in the Pouch

Kangaroos have adapted to the varied conditions across Australia in many ways. One of the most unusual, is the way females of some species can delay the progress of pregnancy. In this way the female is ready to give birth to a replacement for the young in her pouch if it dies early, or within a week of when it permanently leaves the pouch. This ability to delay births means that there can be up to 12 months between a mating and the birth of the young one resulting from that mating (when the normal gestation period is less than 35 days). It also means that the species can best respond to periods of drought and plenty.

Species which have this unusual ability normally mate again soon after the female gives birth. The tiny newly born kangaroo (less than 25 mm long) moves unaided into its mother's pouch and attaches itself to one of four teats. During the early stages of pouch life the young is permanently attached to the teat, but as it matures and begins to grow hair it also develops the ability to release and reattach itself to the teat.

In the late stages of pouch life, once it has a thin covering of fur, the young one begins to explore the outside world for increasing lengths of time until eventually it is old enough to be excluded permanently from the pouch. Complete weaning may take a number of months more after the young has permanently left the pouch. If the mother gives birth during this time, the newborn young will attach itself to a different teat to that being used by the older young. It is remarkable that when this happens the mother produces two different kinds of milk for the two different-aged young^[1].

Origins

The creationist organization Answers in Genesis states the following regarding the evolutionary view of kangaroo origin:

The Macropod family is alleged to have evolved from either the Phalangeridae (possums) or Burramyidae (pygmy-possums)...

However, there are no fossils of animals which appear to be intermediate between possums and kangaroos. Wabularoo naughtoni, supposed ancestor of all the macropods, was clearly a kangaroo (it greatly resembles the potoroos which dwell in Victoria’s forests). If modern kangaroos really did come from it, all this shows is the same as we see happening today, namely that kangaroos come from kangaroos, "after their kind." ^[2]

Creationists believe that there is a lack of transitional fossils showing that the origin of the kangaroo was the result of evolution. They believe that this is not surprising given their view that the fossil record as a whole does not support the evolutionary position. ^[3][4]

According to the origins theory model used by creation scientists, modern kangaroos, like all modern animals, originated in the Middle East^[5] and are the descendants of the two founding members of the modern kangaroo baramin that were taken aboard Noah's Ark prior to the Great Flood. It has not yet been determined by baraminologists whether kangaroos form a holobaramin with the wallaby, tree-kangaroo, wallaroo, pademelon and quokka, or if all these species are in fact apobaraminic or polybaraminic.

Also according to creation science theories, after the Flood, kangaroos bred from the Ark passengers migrated to Australia. There is debate whether this migration happened over land^[6] -- as it is thought that Australia was still for a time after the Flood connected to the Middle East before the supercontinent of Pangea broke apart^[7] -- or if they rafted on mats of vegetation torn up by the receding flood waters.^[6] The theory that God simply generated kangaroos into existence there is considered by most creation researchers to be contra-Biblical.

Other views on kangaroo origins include the belief of some Australian aborigines that kangaroos were sung into existence by their ancestors during the "Dreamtime" ^[8] and the evolutionary view that kangaroos and the other marsupials evolved from a common marsupial ancestor which lived millions of years ago.^[9]

External Links

• Kangaroo facts
• Answers About Kangaroos

References

1. ↑ ^{1.0 1.1} "Kangaroo Biology", Austalian Government
2. ↑ "Kangaroos: God's amazing craftsmanship", Answers In Genesis
3. ↑ Fossil Record Quotes, CreationWiki
4. ↑ "Fossils Questions and Answers", Answers In Genesis
5. ↑ "Kangaroos, Dinosaurs, and Eden", Ken Ham.
6. ↑ ^{6.0 6.1} "How did animals get from the Ark to places such as Australia", Answers In Genesis
7. ↑ "Pangea and the Flood", Apologetics Press
8. ↑ "An Aborigine Creation Story"
9. ↑ "Australian Mammals: Evolutionary Development as a Result of Geographic Isolation"