Remarkable convergent evolution in specialized parasitic Thecostraca (Crustacea)

Yet another case of *remarkable* convergence at the evolutionary level. At what point is there enough evidence to overturn the notion that evolution follows random trajectories.

"Our analyses indicate a convergent evolution of the very similar and highly reduced slug-shaped stages found during metamorphosis of both the Rhizocephala and the Facetotecta. This provides a remarkable case of convergent evolution and implies that the advanced endoparasitic mode of life known from the Rhizocephala and strongly indicated for the Facetotecta had no common origin."

Shaking up the theory of evolution

I've argued for quite some time that current gradualistic evolutionary theory does not square with the fossil record. The fossil record is categorized by long periods of stasis followed by brief periods of the introduction of new species.

This article describes a new theory (which isn't really new as its been talked about in the past) that argues that junk DNA is the primary impetus for speciation.

How crazy is that? Junk DNA once was the tool of the naturalist -- who argued that it was inconsistent with intelligent agency. Meanwhile it turns out that it may be a central component into the origin of species.

"In a co-authored report, due to be published in the prestigious BioEssays journal, the researchers argue that transposable elements (TEs) – or what is colloquially termed jumping genes, selfish or junk DNA, have a critical role in ensuring the survival of biological lineages.

Without this DNA junk, a species is effectively frozen and faces eventual extinction."

Rare tree lobster in a class of its own

Simon Conway Morris once wrote that "convergence might give some surprising insights into a deeper structure of biology, there is some evidence that might at first seem to be simply anecdotal. During my time in the libraries I have been particularly struck by the adjectives that accompany descriptions of evolutionary convergence. Words like 'remarkable', 'striking', 'extraordinary', or even 'astonishing' and 'uncanny' are commonplace... Even convergence suggests to me that there is almost a feeling of unease in these similarities. Indeed, I strongly suspect that some of these biologists sense the ghost of teleology looking over their shoulders... The eeriness of convergence is central to how evolution navigates across the combinatorial immensities of biological 'hyperspace'."

In this article, you'll see yet another example of biological convergence.

"In a paper published today in the Proceedings of the Royal Society B, entomologist Dr Thomas Buckley says DNA testing of tree lobsters from three Pacific Islands shows the Lord Howe Island variety is a separate species.

Buckley, of Landcare Research in New Zealand says the surprising result overturns a long-held view that the Lord Howe Island, New Caledonian and New Guinea tree lobsters come from the same evolutionary lineage.

Instead, Buckley and colleagues found the insects represent three independent evolutionary lineages that had developed similarities through convergent evolution."

Hawaiian honeyeaters' long-lost relatives found

Convergent evolution is one of the patterns that we see in biology that argues that evolution is much more of a constrained process than sometimes recognized.

"Despite appearances, Hawaii's five species of recently extinct songbirds known as honeyeaters bore no close relationship at all to the honeyeaters found in Australia and New Guinea, according to a genetic analysis reported online on December 11th in Current Biology, a Cell Press publication. Rather, similarities in the way the two groups of birds act and look – including their long bills and brush-tipped tongues specially adapted for gathering nectar – arose independently in the two geographical regions.

The unexpected discovery makes the two groups of honeyeaters a particularly striking example of convergent evolution, the researchers said. Indeed, the Hawaiian honeyeaters include three distinct "morphotypes," each of which is also represented by honeyeaters of Australasia. Convergent evolution refers to the evolution of similar traits in distantly related taxa as a result of common selective pressures imposed by their environments."

Model unravels rules that govern how genes are switched on and off

Some evolutionists used to argue that junk DNA was proof that our genome had been constructed sloppily - and is the result of undirected, inefficient processes.

The fact of the matter is that this junk (non-coding) DNA has quite a bit of purpose...

"Since the discovery of DNA's double helical structure more than a half century ago, scientists have focused much of their attention on understanding the 2 percent of the genome that is made up of classic genes, which code for the production of proteins.

However, the instructions for turning these genes on or off are generally not in the genes themselves. Rather, they are buried in the 98 percent of the genome that was once cast aside as little more than genetic "junk."

New Clam-Like Robotic Anchor for Ships

"Experts from the Massachusetts Institute of Technology (MIT) have been able to use biomimetics (the science that adapts natural features for human use) in order to come out with a small item that would hold ships steady. The device, called RoboClam, is very light and no larger than a cigarette, and imitates the foot of a razor clam, Ensis directus, by rapidly digging itself in the seafloor or anchoring itself to almost anything."

Scientists explore nature’s designs

The field of biomimicry is bringing to light what many of us design proponents have been saying for years -- that nature contains clear examples of design.

"Both man-made and sponge glass fibers “guide light,” said Aizenberg, but nature does it better. Along the length of a sponge’s glass fiber, spines multiply the efficiency of collecting light from nearby biophosphorescent organisms. “You can think of it as a Christmas tree,” she said. “Not just the tip collects light.”

Venus’ Flower Basket illustrates nature’s grasp of optics, said Aizenberg, but it also offers insight into architecture.

The resilient sponge is made of square cells reinforced by strutlike diagonal buttresses. In fact, a very modern principle of design and civil engineering, she said, “is present in this [cellular] structure.”

Secondary note: While we debate over the mechanisms (Darwinism evolution, supernatural agency, etc), the primary fact is that design exists. Regardless of the mechanism, the naturalist needs to account for this design and the fine tuning that we find in nature.

Scientists at CSHL uncover new RNA processing mechanism and a class of previously unknown small RNAs

The notion of abundant "junk" DNA has been used to undermine the notion of design. The scientific trend however is that non-coding genetic material has been found to serve important purposes in the cycle of life.

Read the article for more..

"And what of the other 98% of the genome? It has been assumed by many to be genetic junk, a massive accumulation of “code” that evolution has rendered superfluous. Now, however, scientists are discovering that the vast bulk of the DNA in our genomes, while it does not “code” for the specific RNA molecules that serve as templates for protein synthesis, do nevertheless perform various kinds of work."

Ancient Sea Predators Shed Skin Secrets

Convergent evolution is once again pointed out in the linked article.

"Predatory reptiles called ichthyosaurs cruised the oceans between 230 million and 90 million years ago. In a classic case of convergent evolution, their body and fin shapes resembled those of today's dolphins, tunas, and great white sharks—the fastest swimmers in the sea. A new study shows that the convergence even extended to the molecular composition of the animals' skin."

Development Puts An End To Evolution Of Endless Forms

The notion that evolution is completely random, that there is no plan or constraint harmonizes well with the atheistic world view. The fact however is that the commonality of convergent evolution suggests that evolution is a highly constrained process.

Simon Conway Morris has described this argumentation in detail in the book "Life's Solution : Inevitable Humans in a Lonely Universe".

This article discusses the biological factors that contribute to convergent evolution.

"The findings presented in this study also bear directly on issues of convergence (when very different organisms independently evolve similar features). By including a model of development, rather different genotypes can produce very similar phenotypes. Consequently, convergent evolution, which the vast space of genotypes would suggest to be rare, is allowed to become much more common."