Evolution
If evolution of a man took place in different regions the world the communication adopted the shape of dialects and languages. Hunders of dialetcs or dozens of languages can be found in India . Europe also has so many different languages. All human species smile and weep in the same language. However the language which a women uses for communication is most difficult to understand as man has been trying to understand what a women wanted to say and what she has really said and what she could have said . Language of silence is still the most common…
Some of the earliest plants which evolved to bear seeds Gymnosperms ( like cycads) did not have their ovules covered in the ovary. They called it naked ovules. They were even borne on the leaves in some species which are now represented in fossil records. Covering the ovules in a cover of ovary which is modified leaf in broadest sense was sign of evolution in plants. The primitive angiospersms had big flowers. The ovules once covered in the ovary were hardly visible to male pollens to fertilze…
In the final chapter of the book Complexity: A Guided Tour, Mitchell gets to the heart of the real issues that I've been griping about in this blog. She begins by citing a harsh, 1995 piece by John Horgan, “Is Complexity A Sham?”
The article contained two main criticisms. First, in Horgan’s view, it was unlikely that the field of complex systems would uncover any useful general principles, and second, he believed that the predominance of computer modeling made complexity a “fact-free science.”
These are still the main criticisms many have, including myself. Maybe there are common or general…
Another instance of a misleading passage in Complexity: A Guided Tour:
Another example where Evo-Devo is challenging long-held views about evolution concerns the notion of convergent evolution. In my high school biology class, we learned that the octopus eye - greatly different in morphology - were examples of convergent evolution: eyes in these two species evolved completely independently of one another as a consequence of natural selection acting in two different environments in which eyes were a useful adaptation.
However, recent evidence has indicated that the evolution of these two eyes…
A quote from an extremely mediocre book, Complexity: A Guided Tour. Like most people coming out of the 'complexity sciences', the author has a mediocre grasp of molecular biology, both current developments, and the history of the field. It's frustrating that these network people keep hyping supposedly new revolutionary discoveries made the past 10 years of the genome era - discoveries, that in fact have been known for decades. For people clearly new to biology, molecular biology before the year 2000 was a big black hole of ignorance.
There are several claims that make me angry in this book,…
My recent article The Origins of Virtue sparked a discussion in which Josh Witten has assumed that Gerhard Adam and I are confused as to the subject of genic selection. The confusion lies entirely with Josh, but the matter deserves clarification for readers.Gerhard and I (I hope I’m not putting words into Gerhard’s mouth that he would find unpalatable!) have no problem with the purely technical aspects of genic selection. The problem arises when conclusions are derived from these studies that are of a purely personal nature, mere opinions and prejudices with no scientific basis. As a self-…
In How Many Limbs Should Humans Have? I described my Limb Law, an empirical law I discovered which relates how long an animal’s limbs are to how many limbs it has. This law is explained by virtue of animals having evolved a limb design that minimizes the amount of needed materials to reach out into the world (see links to my academic work in the previous piece).
To see the Limb Law in action, go to my web site where you can play with an animal’s limb length and watch how the optimal number of limbs changes. Roughly speaking, the animal designs you can create in this program are the ones…
A mass extinction of fish 360 million years ago hit the reset button on life, setting the stage for modern vertebrate biodiversity, say researchers writing in PNAS. The mass extinction scrambled the species pool near the time at which the first vertebrates crawled from water towards land. Those few species that survived the bottleneck were the evolutionary starting point for all vertebrates--including humans--that exist today.
"Everything was hit; the extinction was global," said Lauren Sallan of the University of Chicago and lead author of the paper. "It reset vertebrate diversity in every…
A crucial aspect of the complexity approach is how interacting elements produce aggregate patterns that those elements in turn react to. This leads to the emergence of aggregate properties and structures that cannot be guessed by looking only at individual behaviour. Explicitly considering how heterogeneous elements dynamically develop their behaviour through interaction is a hard task analytically, the equilibrium analysis of mainstream (neoclassical) economics being a not neutral shortcut. On the other hand, explicitly considering the dynamics of the process started to be a feasible…