April 10, 2017 | David F. Coppedge

Evolutionists Rattled Over Battle for Earliest Animal

If the latest salvo in a long-standing Darwin debate hits, then the idea of evolution growing more complex with time suffers a big blow.

Sponges or Comb Jellies?

Sponges look simpler than other Cambrian animals. Thinking Darwinly, evolutionists would expect they were the earliest animals. Perhaps sponges sparked the Cambrian explosion, resulting in all those starfish, worms, and corals that burst on the scene, they imagine. That Darwinian thought may be under attack itself, says Live Science, when Laura Geggel asks, what animal represents the oldest branch on Darwin’s tree?

The sponge has long been a crowd favorite because its body is extremely simple when compared with other animals. But a new, detailed genetic analysis revealed that the delicate predator the comb jelly (a ctenophore) evolved first, the researchers in the new study said.

Vanderbilt University pipes in: “Forget sponges: the earliest animals were marine jellies,” reports David Salisbury.

Now, a team of evolutionary biologists from Vanderbilt University and the University of Wisconsin-Madison have devised a new approach designed specifically to settle contentious phylogenetic tree-of-life issues like this. The new approach comes down squarely on the side of comb jellies.

The method and its application to this and 17 other controversial phylogenetic relationships were published online April 10 by the journal Nature Ecology & Evolution.

This counterattack follows close on the heels of the advance of the sponge-bobs, who last month declared in Current Biology that sponges were first. Amy Maxmen in Nature, reporting on the “Battle of the Branches” from the battlefield, says that the sponge-bobs declared sponges the winners by “using an unprecedented array of genetic data to deduce that they were the first to branch off from the animal tree of life.” Both sides seem unwilling to admit defeat.

The Vanderbilt press release claims that 95% of phylogenetic cases resolve well. Looking into the uncooperative 5% with their ‘new approach,’ the genetic detectives led by Antonis Rokas came to this conclusion:

In this fashion they determined that comb jellies have considerably more genes which support their “first to diverge” status in the animal lineage than do sponges.

The Problem With Comb Jelly Ancestors

Maxmen gives one prominent reason why evolutionists don’t want comb jellies first in line:

This arrangement rattled evolutionary biologists because it upended the idea that animal complexity increased over time. It implied that nerves and other characteristics evolved independently in different lineages, and were subsequently lost in sponges. Since then, studies have supported or contradicted the rearrangement, but all have been plagued by problems.

According to their paper, the Rokas team used their new approach to try to resolve other contentious phylogenetic relationships. The press release explains:

Another contentious relationship the researchers addressed was whether crocodiles are more closely related to birds or turtles. They found that 74 percent of the shared genes favor the hypothesis that crocodiles and birds are sister lineages while turtles are close cousins.

In the course of their study, they also discovered that in a number of contentious cases, one or two “strongly opinionated genes” among all the genes being analyzed appear to be causing the problem because the statistical methods that evolutionary biologists have been using are highly susceptible to their influence.

In some cases, such as controversies regarding the origins of flowering plants and modern birds, they determined that the removal of even a single opinionated gene can flip the results of an analysis from one candidate to another. In cases like this, the researchers were forced to conclude that the available data is either inadequate to support a definitive conclusion or it indicates that the diversification occurred too rapidly to resolve.

“We believe that our approach can help resolve many of these long-standing controversies and raise the game of phylogenetic reconstruction to a new level,” Rokas said.

—a new level of hostility, perhaps. If relationships can flip over a single ‘strongly-opinionated gene’, all indications are that the battle will wage on. The strongly-opinionated rivals can always argue about which gene needs flipping.

Notice the revealing term Rokas used: “the game of phylogenetic reconstruction.” Evolutionists are fond of using game theory to show how evolution works, so let’s follow their example. Our game theory: the rival teams of evolutionists need to continue their battleship games to avoid boredom.

Games of chance never really resolve to “the truth” about something. That’s why neo-Darwinism, the incarnation of the Stuff Happens Law, provides endless fun for the gamers. Notice what one of the jelly-first evolutionists says in the Nature article: “’By chance, lineages accumulate genetic similarities not due to a shared history but due to random change,’ explains Michaël Manuel, an evolutionary biologist at the Institute of Biology Paris-Seine, and the study’s senior author.”

Keep rollin’ those dice. Give them to Popeye (4/01/17); maybe he will come up with snake eyes.

 

 

 

 

 

Comments

  • tjguy says:

    This is not science. This is a game of who can come up with the most convincing story to explain the current data that we have. It’s a game of interpretation.

    They assume there is a relationship between crocodiles, turtles, and birds and then look at the genes to try and figure out which is closer. One is bound to be closer than the other, but that does not mean they are genetically related to one another in a Darwinian way. It just means that two species have more of the same genes than the other two.

    But if, depending on what genes you look at, the story changes, then you have a BIG problem! Perhaps the assumption of an evolutionary relationship between the two is where the problem lies.

Leave a Reply