I'm from Missouri

This site is named for the famous statement of US Congressman Willard Duncan Vandiver from Missouri : "I`m from Missouri -- you'll have to show me." This site is dedicated to skepticism of official dogma in all subjects. Just-so stories are not accepted here. This is a site where controversial subjects such as evolution theory and the Holocaust may be freely debated.

Name:
Location: Los Angeles, California, United States

My biggest motivation for creating my own blogs was to avoid the arbitrary censorship practiced by other blogs and various other Internet forums. Censorship will be avoided in my blogs -- there will be no deletion of comments, no closing of comment threads, no holding up of comments for moderation, and no commenter registration hassles. Comments containing nothing but insults and/or ad hominem attacks are discouraged. My non-response to a particular comment should not be interpreted as agreement, approval, or inability to answer.

Monday, April 06, 2009

Creatures that defy coevolution are shortchanged by DVD series


The first DVD of a three-DVD series

====================================

The American Family Association is selling a series of three DVD's titled "Incredible Creatures That Defy Evolution". These DVD's neglect some of the best examples of "incredible creatures that defy evolution": creatures that defy coevolution.

Coevolution is generally defined as adaptation to other kinds of organisms, as opposed to adaptation to widespread fixed physical features of the environment (e.g., air, water, and land in its various forms). Because of the prefix "co," which means mutual or together, coevolution is sometimes more narrowly and more properly defined as the evolution of obligate mutualism, e.g., the relationship between bees and flowers, but the definition is often extended to include interspecies relationships where the adaptation might be on only one side, e.g., some predator-prey and parasite-host relationships. Sometimes organic features of an environment -- e.g., the trees of forests -- may for the purpose of evolutionary analysis be treated the same as purely physical fixed features of the environment, e.g., air and water.

As I have pointed out many times, the problems of coevolution present some of the biggest barriers to Darwinian evolution. However, none of the following examples given on the homepage of these DVD's website concerns coevolution -- with the exception of the bird that can kill a lion with a single kick (not an example of obligate mutualism):
.
- Are there really creatures that produce fire to defend themselves?

- How does a giraffe get a drink without causing lethal blood pressure to his brain?

- How can Geckos walk upside down, even on glass and not fall?

- How can birds navigate over thousands of miles of ocean and never get lost?

- How do fireflies and glowworms create light that generates no heat?

- How do great whales dive to the bottom of the ocean without the pressure causing them to implode?

- What creature was the inspiration for the helicopter?

- How can some creatures be cut in half and still regenerate themselves? Some can even grow a new head!

- What kind of bird can kill a lion with a single kick?

- How can some dogs know that a storm is coming before it appears, or can sense when their masters are about to experience a seizure?

- Which creature perlexes scientists because of its amazing ability to heal itself, even when it sustains horrendous injuries?

- How do Emperor Penguins go two and a half months without eating or drinking?

Animals featured in each of the three DVD's are listed below. Of these animals, I recognize only the hummingbird and the melipona (misspelled "milopina") bee as having an interspecies relationship (both are pollinators), though there may be other such animals in the lists.

The first DVD features,

Bombardier Beetle
Giraffe
Woodpecker
Australian Incubator Bird
The Chicken Egg
Platypus
Black & Yellow Garden Spider
Gecko & Chuckwalla Lizards
Human Eye & Ear Drum

The second DVD features,
Whales
The Pacific Golden Plover
Dragonflies
Hippopotamus
Glowworms and Fireflies
Bears
Earthworms
Elephants
Education Dishonesty section
Sparrow

The third DVD features,

Lampsylis Mussel
Horses
Ostrich(e)s
Hummingbirds
Vestigial Organs
Dogs
Manatees
Elephants
Butterflies
A section on designs and designers
Cuttle Fish
Penguins
Milopina Bee and vanilla (correct spelling is "melipona")

Coevolution defies evolution in the following ways:

(1) Obligate mutualism: In the coevolution of corresponding co-dependent traits in obligate mutualism, unlike in evolutionary adaptation to widespread fixed physical features of the environment, there might be nothing to adapt to because the corresponding co-dependent trait in the other kind of organism is likely to be locally absent.

(2) Complex specific adaptations to other organisms: Examples of such adaptations are: orchids' mimicry of female wasps' sex pheromones, some very complex parasitisms

(3) Multi-host parasitisms: These parasitisms may require the simultaneous evolution of two or more parasitic adaptations and it may be difficult to imagine a pathway for such evolution.

Buzz pollination[1] , orchids' mimicry of female wasps' sex pheromones [2], and extremely complex and/or multi-host parasitic relationships [3] [4] would all make good additions to these DVD's.

Here is an example of an extremely complex parasitism, from "The Loom" blog of Carl Zimmer --


As an adult, Ampulex compressa seems like your normal wasp, buzzing about and mating. But things get weird when it's time for a female to lay an egg. She finds a cockroach to make her egg's host, and proceeds to deliver two precise stings. The first she delivers to the roach's mid-section, causing its front legs buckle. The brief paralysis caused by the first sting gives the wasp the luxury of time to deliver a more precise sting to the head.

The wasp slips her stinger through the roach's exoskeleton and directly into its brain. She apparently uses sensors along the sides of the stinger to guide it through the brain, a bit like a surgeon snaking his way to an appendix with a laparoscope. She continues to probe the roach's brain until she reaches one particular spot that appears to control the escape reflex. She injects a second venom that influences these neurons in such a way that the escape reflex disappears.

From the outside, the effect is surreal. The wasp does not paralyze the cockroach. In fact, the roach is able to lift up its front legs again and walk. But now it cannot move of its own accord. The wasp takes hold of one of the roach's antennae and leads it -- in the words of Israeli scientists who study Ampulex -- like a dog on a leash.

The zombie roach crawls where its master leads, which turns out to be the wasp's burrow. The roach creeps obediently into the burrow and sits there quietly, while the wasp plugs up the burrow with pebbles. Now the wasp turns to the roach once more and lays an egg on its underside. The roach does not resist. The egg hatches, and the larva chews a hole in the side of the roach. In it goes.

The larva grows inside the roach, devouring the organs of its host, for about eight days. It is then ready to weave itself a cocoon -- which it makes within the roach as well. After four more weeks, the wasp grows to an adult. It breaks out of its cocoon, and out of the roach as well . . . .

. . . . [the adult wasp] is too small to drag a big paralyzed roach into its burrow. So instead it just delicately retools the roach's neural network to take away its motivation. Its venom does more than make roaches zombies. It also alters their metabolism, so that their intake of oxygen drops by a third. The Israeli researchers found that they could also drop oxygen consumption in cockroaches by injecting paralyzing drugs or by removing the neurons that the wasps disable with their sting. But they can manage only a crude imitation; the manipulated cockroaches quickly dehydrated and were dead within six days. The wasp venom somehow puts the roaches into suspended animation while keeping them in good health, even as a wasp larva is devouring it from the inside . . .

Scientists don't yet understand how Ampulex manages either of these feats. Part of the reason for their ignorance is the fact that scientists have much left to learn about nervous systems and metabolism. But millions of years of natural selection has allowed Ampulex to reverse engineer its host. We would do well to follow its lead, and gain the wisdom of parasites . . .

Yet Carl Zimmer dismisses this "reverse engineering" as merely "an evolutionary transition":

I find this wasp fascinating for a lot of reasons. For one thing, it represents an evolutionary transition.

A summary of my thoughts about coevolution is here.
.

Labels:

0 Comments:

Post a Comment

Links to this post:

Create a Link

<< Home