Sunday, July 29, 2007

A creationism vs. evolution discussion,. Part 8B

Not a hard nut to crack…

Now, back to more of explanations from Answers in Genesis as to why carnivores should, in a pinch, be able to go back to eating fruits and vegetables…

Palm vultures
In their article on palm vultures, AiG claims that the palm nut vulture uses the same tool that other carnivorous vultures have- a sharp beak- to consume palm nuts rather than meat. It states that “Perhaps such observed behaviour is a legacy of a time when animals and birds gorged themselves peaceably on 'every green plant',” and implies that other carnivores can be vegetarian as well-“many pet owners speak of the capacity of meat-eating animals to live on vegetarian diets”- a claim we will be returning to later.

Unfortunately, the link that AiG provides to its source of palm vulture information, is defunct. The article, now found here, tells a bit of a different story than what AiG claims. While AiG states “But for the palm nut vulture, oil palm husk is such a favoured food, that when it is available, all meat options are rejected,” this article states “The Palm Nut Vulture eats the husk of oil palm nuts and raphia fruit husks as well as wild dates, upas and some other fruit. It also eats crabs, molluscs, etc, picked up on the sea shore, and stranded and occasionally live fish which are snatched from the water surface. Giant snails and locusts also feature occasionally. The diet of the adult will be up to about 60% fruits”.” Nowhere does it state “all meat options are rejected.”

In reality, palm nuts are not what we typically think of when we imagine “every green plant”- nutritionally, they are far different from leafy vegetables or most fruits. Palm nuts, like many other nuts, are an extremely rich source of fat and protein, made easily accessible because the oil-rich layer is on the outside of the fruit, not inside a hard shell like other nuts. Oil palm nuts are, as one would expect, even richer in oils than most other palm nuts. In addition, unlike most other fruits, palm fruits stay on the tree for long periods of time and are available when other nutritious foods are scarce. As one expert on the topic noted, “Clearly, the fruits of palms, often rich in oils or carbohydrates, have not gone unnoticed by hungry animals.”

Palm nuts are such a valuable food source that even animals who do not normally eat other plant material will feed on them. One study in Brazil (Seasonal Variation In Fruit Pulp Consumption And Fruit
Removal Of Syagrus Romanzoffiana- (Arecaceae) By Non-Flying
Terrestrial Mammals In A Semi-Deciduous Forest Fragment In
Botucatu, Sao Paulo, Brazil, found here ), for example, found that animals that were attracted to and consumed palm fruits included mountain lions and tayras (a type of weasel.) Another review, just of new reports of palm-seed eaters made since 1989, added maned wolves, badgers, coyotes, bush dogs, dung beetles, and caracaras (a falcon relative) to the list, along with hundreds of other species.

In one fascinating study, when oil palms were planted in a region of Colombia, in which they are not native, local black vultures began to feed on the fruits, and even ignored carrion left out in an attempt to lure them away from the plantations.

So, in closing, palm fruits are a rich source of nutrients, and it is far from unusual for otherwise- carnivorous animals to use them as a food source. A vulture that eats palm nuts is in no way physiologically equivalent to one that lives on lettuce.

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