Organismal biologists needed to interpret new trees of life

Jul 16, 2014

Rapidly accumulating data on the molecular sequences of animal genes are overturning some standard zoological narratives about how major animal groups evolved. The turmoil means that biologists should adopt guidelines to ensure that their evolutionary scenarios remain consistent with new information—which a surprising number of scenarios are not, according to a critical overview article to be published in the August issue of BioScience and now available with Advance Access.

The article, by Ronald A Jenner of the Natural History Museum in London, describes how evolutionary trees inferred from genomic information have overtaken and even displaced traditional studies of animal forms. The traditional studies sought explanations for how the body plans of the three dozen or so major most likely evolved, but molecular data provide strong evidence about genealogical relationships without yielding explanations. So even though data are accumulating as researchers study more and more , there remain severe limits on researchers' ability to construct satisfying accounts of how diverse animal forms evolved.

The difficulty arises because the major evolutionary changes that established the principal animal groups occurred in the remote past, and there are too few surviving intermediate forms to infer evolution's steps in detail. This has sometimes led zoologists to give imagination too free a rein when they devise their hypotheses, Jenner argues. In other cases, new data have forced biologists to accept accounts they had previously found unimaginable. Imagination will remain important in evolutionary studies, Jenner stresses, but biologists will best advance science if they ensure their proposals are consistent with evolutionary trees that are well supported by molecular data, if they look for incompatible evidence and obvious difficulties, and if they evaluate alternative scenarios, as well as their preferred ones. They should also examine the basis of their intuitions and build their ideas of the broadest possible base of evidence, including, for example, that from newly discovered fossils and from new anatomical information. New fields of inquiry offer hope that progress will be made, but "we desperately need" well-funded organismal biologists to achieve it, according to Jenner, not just bioinformaticians and molecular evolutionists.

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Vietvet
5 / 5 (1) Jul 16, 2014
And here comes verkle in -----1----2---3

Torbjorn_Larsson_OM
5 / 5 (1) Jul 18, 2014
Indeed. Science progression means creationist digression. After millenniums of religious magic unwarranted privilege it doesn't know how to wither and die with honor. Ergo verkle.
JVK
1 / 5 (2) 3 hours ago
Why do ..."we desperately need" well-funded organismal biologists...?

With no funding our 1996 model of cell type differentiation via alternative splicings of pre-mRNA and amino acid substitutions attests to the ignorance of biologically-based facts that is touted in the context of mutation-initiated natural selection and the evolution of biodiversity.

Evolutionary theorists seem unable to recognize the fact that ecological variation must be linked to ecological adaptations via cell type differentiation before what they think is "natural selection" occurs. What we need is for evolutionary theorists to educate themselves and accept the biological facts that link conserved molecular mechanisms in species from microbes to man.

From Fertilization to Adult Sexual Behavior http://www.hawaii...ion.html

Nutrient-dependent/pheromone-controlled adaptive evolution: a model.
http://www.ncbi.n...24693353
JohnGee
5 / 5 (1) 2 hours ago
Damn almost got in before JVK.
cjn
5 / 5 (1) 2 hours ago
I've seen how genomics is having a radical impact in bacterial cladistics, so it makes sense that it would have a similar impact on "higher" animal clade formation. I feel like this shift in approach is analogous mental jump of targeting the transcriptome of an organism rather than the genome to truly determine what drives phenotypic expression. I'm excited to see where our phenotypic cladistics have masked the "true" genomic and evolutionary history of life.
JVK
1 / 5 (1) 1 hour ago
There is no evolutionary history of life. Ecological variation results in ecological adaptations that exemplify the biodiversity of nutrient-dependent pheromone-controlled reproduction, which occurs via conserved molecular mechanisms in species from microbes to man.

Those who insist on using terms associated with mutation-initiated natural selection and the EVOLUTION of biodiversity have failed to provide experimental evidence of biologically based cause and effect, which I detailed in a series of publications.

Note: Israeli middle-school education recently changed. They now teach the theory of evolution to show the difference it makes in the context of what is known about ecology. Simply put, ecological facts eliminate evolutionary theory from any further consideration whatsoever. The Israelis obviously want students to be informed, not misinformed by theorists.

http://www.educat...olution/
JVK
1 / 5 (1) 1 hour ago
Science progression means creationist digression.


"I am a creationist and an evolutionist." Dobzhansky (1973) in "Nothing in Biology Makes Any Sense Except in the Light of Evolution" Link opens pdf: http://img.signal...nsky.pdf

What is currently known about amino acid substitutions that differentiate cell types revises Dobzhansky's title.

Nothing about molecular biology makes sense in the light of evolution. Biodiversity is clearly nutrient-dependent and pheromone-controlled. It is not the result of mutations and natural selection. Dobzhansky could not have known that, but the facts continue to be ignored by those who should know what Dobzhansky did. Amino acid substitutions, not mutations, differentiate cell types in primates and all other species. Life is biophysically constrained; it did not arise via mutations and mutations cannot cause biodiversity because they perturb protein folding.
anonymous_9001
5 / 5 (1) 1 hour ago
mutations cannot cause biodiversity because they perturb protein folding


This is directly refuted by induced mutagenesis experiments. Not all mutations have drastic negative effects.
Whydening Gyre
5 / 5 (1) 1 hour ago
It is clear JVK wishes to revise the definitions of some words and meanings in the English language...
cjn
5 / 5 (1) 1 hour ago
There is no evolutionary history of life. Ecological variation results in ecological adaptations that exemplify the biodiversity of nutrient-dependent pheromone-controlled reproduction, which occurs via conserved molecular mechanisms in species from microbes to man.


So let me get this straight: If I were to take an undifferentiated cell from a feline embryo (assume the first initial cell fertilized) and implant it into a dog -assuming that it was possible-, then the product would be a dog at birth? You know, since the cells were exposed to the same nutrients and pheromones.
Whydening Gyre
5 / 5 (1) 57 minutes ago
mutations cannot cause biodiversity because they perturb protein folding


This is directly refuted by induced mutagenesis experiments. Not all mutations have drastic negative effects.

Correct. Given that, if a mutation does not immediately kill an organism, the epigenetics of that organism have a chance to "adapt" and pass that adaptation on to the next generation. So, apparently, mutation IS a driver. Not the only one, to be sure...
CJN - it would more likely be a dot or a cog...