Saturday, February 18, 2006
Considerations of the Natural History of Animals, Their Characteristics, Their Interrelationships, Their Organic Structure, Their Distribution, Their Classification and Their Species
On the Role of Art in the Productions of Nature
The Importance of Considering Affinities
Concerning Speciation in Living Things and The Idea We Should Attach to This Word
General Observations on Animals
On the Present State of the Distribution and Classification of Animals
The Degradation and Simplification in Organic Structure from One Extreme to the Other of the Chain of Animal Life, from the Most Complex to the Simplest
Concerning the Influence of Circumstances on the Actions and Habits of Animals, and the Influence of the Actions and Habits of these Living Bodies As Causes Which Modify Their Organic Structure and Their Parts
Concerning the Natural Order of Animals and the Arrangement Which Must Have Led to Their General Distribution to Make it Conform to the Very Order of Nature
[Lamarckian, Zoological Philosophy]
Friday, February 17, 2006
[King & Wilson, Science, Apr '75]"Their macromolecules are so alike that regulatory mutations may account for their biological differences"
(No Abstract Available: Related Terms include Mary-Claire King, Wilson, DNA and Genetics, the Genome, Human and Chimpanzee)
Thursday, February 16, 2006
Info wanted on two intriguing 'Lamarckian' experiments
"Fifty years ago, for instance, one Harry Schroeder conducted an intriguing experiment with the willow-moth caterpillar. This caterpillar places itself on a leaf and rolls the leaf around itself before pupating, fastening it down with a web.
Normally, it starts by drawing the tip of the leaf over itself, but Schroeder, with fiendish cunning, systematically cut off the tips of all the leaves on which caterpillars had taken up position. Sensibly enough, they responded by drawing the side of the leaf over instead.
When these caterpillars had produced another generation, Schroeder found that, of nineteen offspring, four drew the side of the leaf over, not the tip, when their time to pupate came around.
It may be said that this was inheritance of an acquired behavior, not a structure, but there may not be much difference from a genetic point of view, as we shall see.
Perhaps the same might be said of an unique series of experiments by Frederick Griffiths, who placed rats on slowly revolving turntables for periods of up to one and a half years. When the wretched animals were freed their heads constantly flicked in the direction in which they had been rotated, and their eyes flicked also. This flicking automatism reappeared in their progeny."
Both of the above experiments exhibit characteristics consistent with the proposed homeostatic internal evolutionary mechanism I am currently researching. Unfortunately, however, Taylor gives no citations and there are no further references to Schroeder and Griffiths in either the Bibliography or the Sources.
Should anyone comes across any information regarding these experiments - or others of a similar nature - I would be very grateful if you could let me know: firstname.lastname@example.org
"The Great Evolution Mystery" is no longer in print although used copies are still listed on these pages of Amazon.com and Amazon.co.uk
[Related terms: Lamarck and Lamarckian]
*This is an update of evomech message #43:
--Model of an Internal Evolutionary Mechanism:
technorati tags: great+evolution+mystery, evolution, willow-moth, caterpillar, gordon+rattray+taylor, experiments, rats, lamarck, lamarckian, acquired+behavior, internal+evolutionary+mechanism, schroeder, griffiths, john+latter
Wednesday, February 15, 2006
[Editor's note: This essay will be published in the Spring 2006 issue of VQR in a special portfolio on Darwin, evolution, and intelligent design. The portfolio will also feature essays by Michael Ruse, Thomas Eisner, and Robert M. Sapolsky, and an excerpt from David Quammen's forthcoming book The Reluctant Mr. Darwin: An Intimate Portrait of Charles Darwin and the Making of His Theory of Evolution. To pre-order the Spring issue, click here.]
"I came to evolution in a roundabout way. Sure, as a kid I had seen the dinosaurs at the American Museum of Natural History - and had heard a bit about evolution in high school. But I was intent on studying Latin and maybe going to law school.
But evolution got in the way... "
Full text at:
technorati tags: darwin, vqr, virginia+quarterly+review, niles+eldredge, evolution, intelligent+design, michael+ruse, thomas+eisner, david+quammen, theory+of+evolution, dinosaurs, natural+history, museum
Tuesday, February 14, 2006
Gene Regulatory Networks and the Evolution of Animal Body Plans
Development of the animal body plan is controlled by large gene regulatory networks (GRNs), and hence evolution of body plans must depend upon change in the architecture of developmental GRNs. However, these networks are composed of diverse components that evolve at different rates and in different ways. Because of the hierarchical organization of developmental GRNs, some kinds of change affect terminal properties of the body plan such as occur in speciation, whereas others affect major aspects of body plan morphology. A notable feature of the paleontological record of animal evolution is the establishment by the Early Cambrian of virtually all phylum-level body plans. We identify a class of GRN component, the 'kernels' of the network, which, because of their developmental role and their particular internal structure, are most impervious to change. Conservation of phyletic body plans may have been due to the retention since pre-Cambrian time of GRN kernels, which underlie development of major body parts.
Reprints available from Eric Davidson at the email address on the following link (or contact email@example.com):
Model of an Internal Evolutionary Mechanism
A leading evolutionist recently observed that the great questions in evolutionary theory
remain much the same today as they were in Darwin’s time. Certainly this observation
applies to the debate over the inheritance of acquired characters, commonly known as
Lamarckism, after Jean Lamarck, author of the first systematic theory of evolution. The
debate over the reality of Lamarckian ideas has raged for the better part of a century and
a half and shows no signs of abating. Indeed, as I write, the controversy has been
rekindled over the announcement of new experiments allegedly supporting the possibility
of inheritance of acquired characters.
In an attempt to understand the historical background and theoretical significance of this
controversy we will offer here a brief outline of the history of the inheritance of acquired
characteristics. This outline will include a summary of Lamarck’s theory of evolution; an
assessment of the validity of its rejection by Weismann and Neo-Darwinism; and a
discussion of recent developments including the modern revival of the inheritance of
acquired characters by Steele and Gorczynski.
Full text at:
Model of an Internal Evolutionary Mechanism
technorati tags: inheritance+of+acquired+characteristics, lamarck, weismann, controversy, steele, evolution
Monday, February 13, 2006
Evolution of phenotypic plasticity: where are we going now? (TREE)
[Puglicci, Trends in Ecology and Evolution, Sept '05]Abstract:
The study of phenotypic plasticity has progressed significantly over the past few decades. We have moved from variation for plasticity being considered as a nuisance in evolutionary studies to it being the primary target of investigations that use an array of methods, including quantitative and molecular genetics, as well as of several approaches that model the evolution of plastic responses. Here, I consider some of the major aspects of research on phenotypic plasticity, assessing where progress has been made and where additional effort is required. I suggest that some areas of research, such the study of the quantitative genetic underpinning of plasticity, have been either settled in broad outline or superseded by new approaches and questions. Other issues, such as the costs of plasticity are currently at the forefront of research in this field, and are likely to be areas of major future development.
Model of an Internal Evolutionary Mechanism:
technorati tags: evolution,, phenotypic+plasticity, pigliucci, research, genetics, molecular
Sunday, February 12, 2006
proposed the concept known today as "The Baldwin Effect":
"In several recent publications I have developed, from different
points of view, some considerations which tend to bring out a certain
influence at work in organic evolution which I venture to call "a new
factor". I give below the list of references  to these
publications and shall refer to them by number as this paper
proceeds. The object of the present paper is to gather into one
sketch an outline of the view of the process of development which
these different publications have hinged upon.
The problems involved in a theory of organic development may be
gathered up under three great heads: Ontogeny, Phylogeny, Heredity.
The general consideration, the "factor" which I propose to bring
out, is operative in the first instance, in the field of Ontogeny; I
shall consequently speak first of the problem of Ontogeny, then of
that of Phylogeny, in so far as the topic dealt with makes it
necessary, then of that of Heredity, under the same limitation, and
finally, give some definitions and conclusions."
"...In this interview with DJ Grothe, he [Dawkins] discusses his newest work, a two-part documentary series for British television entitled The Root of All Evil?, in which he challenges what he calls 'the process of non-thinking called faith'..."
While disagreeing with Dawkins' perception of how evolutionary changes occur I do feel he has something to say regarding 'faith'. Not least because belief in a theory can have similar origins to belief in a God - I'm reminded of this every time someone says "Evolution does this.." or "Natural Selection does that.."!
And for anyone arguing alternative or new explanations contrary to perceived wisdom it can be useful to understand the nature of the resistance encountered:
"If you know the enemy and know yourself, you need not fear the result of a hundred battles.
If you know yourself but not the enemy, for every victory gained you will also suffer a defeat.
If you know neither the enemy nor yourself, you will succumb in every battle."
(The Art of War, Chapter 3:14, Sun Tzu Wu, 536-496 BC)Some of the issues Dawkins raises also have a particular topical relevance:
Evolution: The Horse Whisperer, Richard Dawkins, and Danish Cartoons