Evolution, Morphology and Exobiology

Hi, Correct me if I'm wrong, I'm new to this. Genetic mutation happens randomly, and natural selection decides the direction, i.e, lets the advantageous continue their lineage. I'm not comfortable with the genetic mutation part. It seems to me that mutation it is too coincidental that forming new traits isn't really possible. Don't you think there should be a system like adaptive-mutation [which is generally not accepted, right ?], or some other system that reduces the impossibility [to me at least] of mutating new traits . To give an example, say we are in the period where underwater creatures started to develop fins. How does this happen ? Through geneti…

Could such be used in ecological application to discern fitness factors for an organism such as a microbe in an artificial environment? I know its sort of a energy in a system question I think but any reply would be appreciated. I don’t know how precise you can get with fitness in a population of microbes as is down to an individual because more or less I am looking for how such environmental stimulus is received by an organism, such as light or sound with hearing and vision for example. I would like to think this is orientated to seeing fitness in populations from such a scale while trying to identify molecular basis. My questions really is that I don’t understand the r…

This is my Review of "The Edge of Evolution" by Michael Behe. I am reposting it from my blog: http://aigbusted.blogspot.com Ok, here it is: About a week ago I picked up Behe's book, in hopes of reading it and reviewing it, and seeing if the arguments were any good. In his book, Behe argues that Common Descent is a fact, and so is Natural Selection, but he's not so sure about Random Mutation. He admits that it happens, but his point in the book is mainly that random mutation cannot account for what we see today. Unfortunately, Behe didn't sell me on intelligent design, and there were quite a few errors that need to be corrected within the book. Forgive me if th…

This is an attempt to shorten the posts in the thread "Help on Shattering the Myths of Darwinism". This thread will focus on the "scientific" objections Milton and the Advocate raise. Before I start addressing Milton, let's just do a reminder of the 5 different theories that Darwin proposed. These are: "1. The nonconstancy of species (the basic theory of evolution) 2. The descent of all organisms from common ancestors (branching evolution). 3. The gradualness of evolution (no saltations, no discontinuities) 4. The multiplication of species (the origin of diversity) 5. Natural selection." Ernst Mayr, What Evolution IS. pg 86 This is one example …

New paper by Charles Lineweaver---a world-class cosmologist who also does astrobiology. The new paper bears on estimating the possible rarity of extrasolar civilization http://arxiv.org/abs/0711.1751 Paleontological Tests: Human-like Intelligence is not a Convergent Feature of Evolution Charles H. Lineweaver 14 pages, 6 figures, to be published in "From Fossils to Astrobiology" Edt J. Seckbach and M. Walsh, Springer 2008 (Submitted on 12 Nov 2007) "We critically examine the evidence for the idea that encephalization quotients increase with time. We find that human-like intelligence is not a convergent feature of evolution. Implications for the search for extra…

Yes as I am reading math stuffs I happened to pop one of those annoying thoughts I think would make a neat thread. This probably should be in speculations but I don’t understand the customs to such all to well. Okay then. For instance, division, or multiplication. Anyways at all to trace maybe such thoughts naturally occurring, or is such purely artificial as in learn for example? I don’t know how you separate learning from natural to artificial its more or less a shoddy mechanism for communicating but its the best I could do. For example, gauging the velocity of an object. Does this naturally occur by instinct with people at some age cutoff? The only way I …

I don't get why some people don't believe that evolution is real. Why do people think evolution is fake? or is asking it like asking a godwad why they believe in god? im also wondering if evolving could mean having genetic mutations because in every movie that has anything to do with evolution they say that it means to mutate, i used to think they just said this because they just didnt know what evolution meant but there are so many writers out there that write about it like this and they are all full grown adults and im a teenager so i probably am wrong and not them by the way you probably guessed already but my knowledge of genetics is the same as a seventh grader's

Awesome video of a computer simulation showing the evolution of watches that can keep accurate time from random initial starting configurations: http://scienceblogs.com/pharyngula/2007/10/how_to_evolve_a_watch.php

Let's say you have two mammals who are the only two in their Order to share a primitive feature on their molar. Does that in and of itself suggest an affinity between them?

Am I correct in saying that the smaller a life form is, the better probability it has of surviving by evolving to suit the newly emerging environments? As well as a sudden, or, rapidly changed environment? I speculate that humans and other megafauna of the present, will paint themselves into a corner, like the megafauna of the Jurassic period eventually did. This cycle will repeat itself with the physically smaller species evolving into the new megafauna of the future. I’m sure this has been speculated at some point, probably by a guy with a beard . Of course, I'm interested in what thoughts others may have.

Inspired by the Anthropoid Origins thread. I’m not sure if evolutionary theory deals with the mind, but here goes (move it if you must). When did human consciousness as we know it, get to that point, on the scales of evolution? Do you think that consciousness for early man, as we know consciousness, would have been a very gradual, on – consciousness, off – consciousness, spanning generations, type of development. Until it was constantly in ON position during waking hours? Do you think consciousness was suddenly switched on by enviro pressures and accepted by early man as a new, very handy way of perceiving the world? Your views please. cheers

Can anybody point me to a link, or, walk me through the theoretical evolution of the Venus Flytrap (Dionaea muscipula)? Image representations of stages of development would be great. Cheers.

Another primate paleontology thread. I know everyone is excited. This is a debate I've been lately reacquainted with reading Chris Beard's Hunt for the Dawn Monkey. I was wondering if anyone had read the book and/or had any particular opinions to offer on the origins of the Anthropoidea, the suborder of Primates consisting of the monkeys, apes, and humans. I'll attempt to summarize the debate if I might: There are four competing theories that posit which group of the Eocene primates the Anthropoids descended from: The Adapoid Theory: Believes anthropoids descended from lemur-like adapoids. The Omomyoid Theory: Believes anthropoids descended from tarsier-l…

Hey, all. This is my first post on these forums, and it's going to be a doozy! I have two questions: 1) Is The Bell Curve a logical, sound book with reasonable, if unverified, conclusions? 2) Is intelligence heritable, and, if so, is it not reasonable to assume that geographically separated populations will have varying intelligence trends? I know these issues are hot buttons, but I'm hoping you'll help me wade through the bullshit, as it were. EDIT: Oh, I'm putting this thread in the "Evolution" section because it deals with heritability. I would have put it in the psychology section if one existed. The mods can move it if they have a better idea.

"Finds test human origins theory" From the BBC Science and Nature. I don't have access to Nature to read the real article, so I'm just going by the BBC. Here's the New Scientist article that I can only read the first paragraph of. A Professor Spoor, quoted in the article, appears to feel that because of this discovery of Homo erectus and Homo habilis living at the same time, "[The idea that Homo erectus descended from an isolated populuation of Homo habilis] is a much more complex proposition [than peripatric speciation], the easiest way to interpret these fossils is that there was an ancestral species that gave rise to both of them somewhere between two and three…

Has the earth been around long enough for a single celled organism to evolve into a plant or a fish or any other complex animal?

If we're going to go by Mayr's notion (which I like), there are only two valid species concepts: The Biological Species Concept, and a typological species concept. I'm going to assume everyone has a good conception of the BSG, so let me go into depth on the typological concept. A typological species concept uses the phenotypic difference between two animals to define them as separate species. Obviously, all paleospecies are therefore described under a typological concept. We can't get a bunch of hominids together and see if they'll interbreed. So the question is, should paleontologists look at some specific 'diagnostic' features (known as essentialism, or sometimes co…

Probably all the organic beings which have ever lived on this earth have descended from some one primoridal form, into which life was first breathed...There is grandeur in this view of life...that, whilst this planet has gone cycling on according to the fixed law of gravity, from so simple the beginning endless froms most beautiful and most wonderful have been, and are being, evolved. Charles Darwin. Apply for mere scientific beguilement, this conception to Exobiology. Interested in personal qualm or agreement behind acquired residuums.

I am trying to gain a better personal comprehension of evolution (which I generally "understand" fairly well) and one fact that would help me is a ballpark estimation of the number of total primate generations. To clarify A. What is the fastest reproducing primate/ What is the average reproduction for primates----This number by generation as in humans have a new generation ever 20 years ish. OVER B. According to the best knowledge we have when what is the earliest primate known? A - = total generations B Am I missing anything in trying to figure this out? Finding this ballpark figure could help me comprehend how many trials there have be s…

I was reading this article in The Times. http://www.timesonline.co.uk/t.....980396.ece It is arguing that human settlement into communities instead of a hunter gatherer existence took place much earlier than originally thought; about 400,000 years earlier. Any opinions on this out there?

Until yesterday I had always thought that the answer from the palaeontological community was a resounding "yes." I had no idea that there was any decent. I just started reading Ernst Mayr's What Evolution Is, however, and lo and behold, he quite persuasively presented a quite different view. Mayr seems to feel that birds descended from thecodont reptiles of the late triassic, and evolved in parallel to the dinosaurs. He cites the similarity of the pelvises of birds and the bipedal dinosaurs as a remarkable instance of parallel evolution; similar environments acting on similar genetic potentials in related lineages similaraly. I'll summarize his argument by copying…

I hate to be blunt but this seems gobble-gook, can someone please explain in a more general point to what the actual issue is here. Thanks......

If you follow the history of evolution all animals and plants once originated as single celled organisms and have evolved to adapt to their surroundings. But how did these original cells have the genetics or brains to come up with these adaptations? For instance, fair enough that original single cells evolved feelers to grab onto their surroundings, this could have been acheived through mutation. But how does an organism learn that it can view the world on a whole new level through sight and create powerful eyes? At what stage were any parts of a single cell, such as the normal parts of a cell able to presume that light could be seen and what parts started utilis…

Having had this really odd concept brought to my attention via this comic, and trying to learn more from this Wiki' article, I don't understand, how do Axolotls metamorphose? If it's not something they do regularly then how does the mechanism get unlocked on demand?

Did the title work in getting attraction? Anyways, does anyone know any good links of such or thoughts to share on the subject. I personally find it ripe with possibility for studying evolution really. I am not speaking particularly of neoteny studied at a molecular level in regards to the specie but the molecular basis of life itself studied from such a neoteny perspective, such as studying the evolution of a particular chemical structure or function in an organism:confused: I think:D I don’t know if you can separate the two easily. Much thanks in advance.