Evolution, Morphology and Exobiology

Hi! I'm confused in the difference between a stele and a protostele? Thanks

So I am aware that the human nose and ears grow a whole life, so when one is older by consequence, one has a larger nose and ears. I was wondering if this might be natures way of some what compensating for hearing loss and lower lung functions that occur often in old age.

If life on Earth, or intelligent life on Earth never goes extinct, and continues to grow on forever, would it be safe to assume that over a long enough period of time that it would basically consume the universe? Not to evoke some kind of psychological line of thinking but in a sci-fi tone I could actually see at some point the entire universe having to consist of nothing but life if growth continues forever. What do you think?

It is sometimes argued that advances in the medical science, by reducing the mortality due to hereditable diseases, result in building a reservoir of unfavourable genes in the human population, and that this will reduce the viability of the human species. Discuss this statement. I have read a few blogs on this topic but none explain about medical science reducing the viability of the human species. Can you please help me out here, it would really help gaining an understanding of this. Thanks

I'm not sure this is the correct forum, but I like to observe cells with my microscope. I generally use from 200-600 X for my observations, taking pictures which I later enhance with Photoshop. I have never observed stem cells or cells in mitosis(except prepared slides) and was wondering if I could find epithelial cells in these conditions. What power would you use for examining stem cells? Thanks, Paul

I did some research on the air sac breathing system of birds and I found it fascinating... Is it possible for a similar system to evolve in another group like say reptile or mammal?

Hello! I am a student in Estonia and am currently writing a research paper on how the creationism vs evolution debates and issues are affecting society. I would be grateful if you took the time to fill in a small 10-question survey on this subject. I would use the responses to generate statistical information for my paper. The address is: http://www.surveymonkey.com/s/57GMMJR I am sorry if this is considered as spamming, but living in Estonia, it is really difficult for me to get into contact with the target group of my paper (US and UK citizens). Plus, the forum topic seems to be relevant.. I'd really appreciate if you took just a minute or two of your time for…

evolution is just a theory with no proof to back it up, I am one who believes in creation but once again no real proof for that either, in fact I like to think they kind of go hand in hand but as for one animal changing species, there is no transitional fossils to prove this. If evolution were true there would be millions of fossils showing the transition from one animal to the next. Even Darwin said it isn't true, he stated evolution as an animal changing to it's environment, survival of the fittest I guess you could say, and a species changing such as the wolf to poodle transition, same species but different animal. Darwin said animals did not jump species and even said…

If modern macro-evolution ideas are correct why arent there millions of intermideate stages discovered for every creature in existance?

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I need links to help me understand evolutionary biology and zoology. I'm going to start a university course in biology (I'm yet to decide what I wan't to specialise in) and I have no prior knowledge on these topics, apart from the fact that I am deeply interested in them. I took high school biology for granted and now 4 years after graduating I'm starting back at square one. All I need is basic info for an idiot: links, books, academic papers etc. Nothing too complicated just info to get me started then I will branch out into the difficult stuff. Any help, comments or support will be greatly appreciated. Thanks.

Evidence suggests that life appeared very soon after the Earth formed. Right. This means that life can form easily. OK so far. But if life formed so easily, why has it appeared only once in Earth's history? Surely, if it can be produced easily, it should have come up in several places in various forms and the descendants of each life strand would somehow have left evidence of their existence. But there is only evidence of the current life. The only 2 things I can suggest are that: 1) Life appeared at the beginning in many ways and many places on the primordial Earth, but only the current one was selected by evolution. Which then would suggest that the condit…

Chimpanzees use stone tools, and fashion sharpened spears (by chewing). Chimps & Humans diverged, evolutionarily, about 6 million years ago*. * http://en.wikipedia.org/wiki/Chimpanzee ; http://www.buzzle.com/articles/chimpanzee-habitat.html This strongly suggests, that the Last Common Ancestor (LCA) of Chimps & Humans made & used stone tools & spears, before about 6 million years ago. So, seemingly, various creatures have been crafting increasingly sophisticated weapons systems for many millions of years. The spear, specifically, may be much more ancient than typically proclaimed. Possible ? Plausible ?

How do you think prions came about in the natural world? I have considered as of late that it was an odd mutation created by a plant in order to defend itself against herbivores.

Hi guys, I will be totally honest here. I love science and I sincerely wish to understand it. Actually, everything is great and pleasant, math, physics, chemistry, etc. Tons of rational and logical concepts, everything makes sense (well, at least much of it, unless you are an Einstein or some other rare and luminous brain to understand it all). But then I bump into Evolution and a world of mistery and unclearness unveils. So I would like to post some questions on some of those issues that "keep me awake at night" (ok, not really, but you know what I mean). First of all, I'm still to find a believable/logical explanation about the abiogenesis issue, that is, life…

Can someone please explain it to me? Is it arguing against the statement that more genetic variation lies within human populations then between them? When studies of genetic clustering are made like this one Is it the case that a special set of loci are selected that tend to differ more between populations then a randomly selected set?

It it like this? 1. Eukaryote 2. Protist 3. Protozoa I cannot figure it out. I haven't ever really been able to figure it out. I've read the wiki article, but didn't grasp much. Maybe someone can drill this into my head?

Hi can anyone recommend any good books by respected authors on the subject of behavioural modernity? (Or what is otherwise known as 'the great leap forward'). I'm attempting to learn more about this topic, but I don't want to waste my money on poor purchases of inappropriate titles. I also would be up for reading any online books, or watching any videos. Thanks! Merged post follows: Consecutive posts mergedOK, for those not quite familiar with the term: http://en.wikipedia.org/wiki/Behavioral_modernity

I was wondering over this picture.... Do Bats, also have different wing shapes like this?

Hi. Landed birds seem to move their heads in jerks, as if their vision would not work well in uniform motion; and at the same time, they are supposed to have good vision moving in flight... Most walking birds keep the head motionless while the body/legs advance, until repositioning the head in advance and repeating. What is going on ?

Was there any difference in the youngest age the average woman could conceive over the recent millennia? Reading in Shakespeare that "Younger than [14 years old], are happy mothers made," this got me thinking. I had assumed that most cases of pregnancy at a much younger age would be morbid, perhaps even life-threatening. Is it possible that over a mere 500 years there has been evolution in this?

I am just curious about the structure of that hook at the wrist... Is it like a panda's thumb and can be moved independently of the hand?

Is this suggested scenario a plausible explanation ? Darwin's "warm little pond" was a deep water, warm spring, in the Archaean Era 1. Basal Eukaryote evolved in deep ocean warm springs (~2.7 Gya) Alexander S. Bradley, in the article "Expanding the Limits of Life" (Scientific American [Dec. 2009 AD], pp. 62-67), argues that the earliest Earth lifeforms, were primitive chemosynthetic microbes, inhabiting highly alkaline warm [~90 degrees C] spring systems, like the "Lost City" formation, found 15 km west of the Mid-Atlantic Ridge, and consisting of Calcium Carbonate chimneys. In complete contrast, to the more well-known "Black Smoker" systems actually inside th…

Hi I am just wondering how do pterosaurs take off from the ground using all four limbs. http://blogs.ngm.com/blog_central/2009/08/pterosaur-takeoff-.html I still had some doubts so I decided to animate the thing in my computer graphic program. Becos I have a creature design project that needs a creature that can take off using 4 limbs. I need some guy from a scientific viewpoint to see if my animated creature seem plausible. This one is for smaller species... This one is based on references of smaller birds which take off immediately from a standing start. Also smaller species have a lot of wing flapping. This one is for bigger species.. Becos it…

Early in the human history, when the individual could hardly be rendered as human by modern standard, wars or conflicts between tribes were usual. The idea that a member should contribute the tribe but not the rivaling tribe was necessary for sustaining the glory of a tribe. This resulted in the basis for the religion that a member should have as little relationship with a member from other opposing tribes. Punishment was expected for those who betrayed this meme. Under such a condition, a member who remained ‘loyal’ to his tribe would be credited and the opposite would be disregarded, and this would easily favor the emergence of gene, if any, which distinguished between …