Evolution, Morphology and Exobiology

I recently finished reading Richard Dawkins' book "The Ancestor's Tale" and when I reached the end I noticed that the family tree lists (multicellular) plants and fungi as preceding some single-celled organisms such as choanoflagellates and DRIPs. I had always assumed (perhaps naively) that single-celled organisms came first, then multi-celled organisms evolved from them at one point, and that was that. (I understand that single-celled organisms still exist and did not die out when multicellularity appeared on the scene). But unless I'm understanding the book incorrectly, it seems like certain multicellular organisms (e.g. plants and fungi) branched off fro…

I finally have to admit that we are beings of excited atoms via chemical reactions. Microbes are the most experienced biochemists on the planet, although they are not aware of it or even us for that matter. Yet our origin is apparently a fusion event between archaea and eubacteria and later mitochondria that all together made eukaryotes without any directed purpose. Eukaryotes are actually a larger bacterial species since we are made of them, shouldn't we finally admit it to ourselves? We are apparently built from the inside out with genes that automatically were programmed to manufacture engineered proteins and was able to place all of our body parts and its syste…

Eukaryotes are believed to be fusion of an archaea single celled organism and a eubacteria single celled organism that eventually created the nucleus and then consumed a mitochondrial cell which is believed to be actually a proteobacteria cell. The nucleus that protects our DNA is not found in archaea, eubacteria or a proteobacteria organism. In plants, another eukaryote consumed a chloroplast cell which is believed to be actually colonies of cyanobacteria. Further evolution involved acquired retroviruses in addition to cell duplicate and random mutation. This does not appear to be an accident if this is indeed how it happened. All of these single celled organisms in…

The wolbachia bacteria that infects 75% of arthropods is in the process of moving its entire genome into these species. Is this comparable to when mitochondria moved into us?

I am aware of the fact that certain species have evolved physical traits that would reduce the likelihood of them being eaten by predators. E.g. certain insects have evolved to mimic plants so that predators may mistake them as such. However, I have been wondering if any species have evolved a certain trait that makes them more attractive to prey, sort of like a luring system. I am mostly referring to species other than humans or anything biologically related to humans. Perhaps I already know a specific instance of this, but it just eludes me at the moment, so when someone mentions one it may just refresh my memory.

Suppose an alien visitor had come to Earth. Let's also say for arguments sake that this visitor had evolved on it's home planet with eyes that could only interpret and see ultraviolet light. What would he see on our planet? From what I've read the Earth's atmosphere blocks ~98% of the ultraviolet light that our star emits. Would this creature also be "blind" to normal light?

Hey all: I'll start by saying that I'm not utterly ignorant of evolutionary biology--I suppose I have a college-intro-level knowledge of it, and do not subscribe to any particularly goofy theories regarding it. I am aware that the creationists/IDers point to examples of natural selection at work and scream that this isn't evolution, just adjustments in the gene pool, changing frequencies of traits, etc. The example of peppered moths in industrial Britain, I know, has attracted no shortage of hoarse screams. My question is, according to current definitions (or perhaps just current norms) that you might be more in step with than I am, when is it conventional to sa…

Is there any scientists on this forum who studies cells? I am curious of how you view single celled organism, do you see them as actual beings of lifeforms or just simply life cells that react to chemicals and convert chemicals as waste production?

Given said genome of a mammalian species, such as a white tiger, how much is known about the proteins that are involved in its biological development? The proteins used to guide cell differentiation and control the genome in those different cells at different stages? Can it be assumed that all the proteins necessary to sustain and allow cell differentiation exist in the egg and sperm for such a mammal? If so, have scientists taken effort to document such proteins? Is there a database or databases that discuss proteins that are used for developmental processes per particular species?

there is a video game called cellcraft that many people are claiming is a method of pushing creationist views. i have played it and it was a cool game about cellular mechanics. I don't see any creationism in it at all. but maybe i'm being naive. so could someone look at the facts in this game and confirm or dis-confirm them? and could someone tell me what about this game is incorrect unverifiable or strays out of mainstream science in anyway? I get that some creationists worked on it but it seams like it would be easy for a non-creationist to review it and make a conclusion based solely on its content on weather or not it is a viable teaching tool for teaching MAI…

We should be directing more of our resources into breeding the perfect spider, bigger than a Goliath Birdeater, and more aggressive/venomous than a Brazilian Wandering Spider/Sydney Funnel-web., and more adaptable than any spider, can live virtually anywhere except the frozen north/south The largest spider is often compared to being the size of a dinner plate, well we should be aiming to increase the size to that of a truck tire. Sydney Funnel-webs are typically a pretty pissed off spider, but we could possibly encourage their body to release a lot of natural steroids into their system, give them some roid rage to play around with, that coupled with the face that the …

( my first language isnt english so im sorry if theres alot of spelling errors ) first off im not a religious man and i DO " belive " in evolution theory, just to ease everone's mind My knowledge admittedly on this topic is limited to what ive read in a few books/magazines and seen in documentaries so i am well aware that these questions may have been answered without me knowing it. My question is about forknowledge, or what to me seems like forknowledge. First i have hard time getting my head around how the first watercreatures could make the jump to land. How did they succesfully "aquire" the biology to survive in an enviroment it had not yet experience…

I'd like to see an Urey-Miller type experiment done except substituting boron hydrides for methane or other carbon compounds. It would have to be done in cold and or highly pressurized conditions so the ammonia would be liquid with just a small amount of water dissolved in the liquid ammonia. http://en.wikipedia.org/wiki/Miller%E2%80%93Urey_experiment Possibly to test some of this.... http://www.daviddarling.info/encyclopedia/B/boron-based_life.html

Or better said, the hen and the egg. All living creatures go to a great extent in conserving energy, finding food and not wasting resources is an activity that takes most of their time. Non-fertile eggs laid by hens are a huge waste of resources, food and energy. Is there an explanation, please ?

There have been a lot of threads about the validity of Evolution, and well I'm going to post all the evidence that I know and from my biology texts so that there will be no confusion. I wouldn't like to over-step my bounds, but I would like to invite others to post on this thread other evidence or insights that I have missed (I hope to just cover the basics with this first post) and we could possibly use this as a reference in the future. What is Evoltuion?? Evolution is the change of a population of a species over time, or if you prefer the change of alleles over time. Evidence of Evolution Fossil Record Fossils provide a record for species that have lived in…

http://www.youtube.com/watch?v=uW7NlkKaF38 It's an anti ID vid showing Dawkins and some others dissecting and talking about the recurrent laryngeal nerve in a giraffe. Fascinating dissection to watch, especially from an evolutionary point of view because that nerve does not make sense from anything but an evolutionary point of view. But as the title suggests, what other poor designs do we have, which are in the realm? I don't think Wisdom teeth really cut it.

I have heard that pterosaurs can change the shape of their wing membranes... How is this possible? Can Bats do that same like say use wing fibers to control the shape of their membranes

OK it's a dumb question... because they have gills! But aren't those gills just extracting oxygen from the water already? I would have personally thought that even though water may be more oxygen rich (being hydrogen and 2 oxygen atoms after all) that air would have been easier to extract the oxygen from as it's already freely floating around and therfore no need to seperate the 02 from something I'm no biology expert so I thought i'd better ask this burning question on SFN before I forgot I was curious about it.

I was wondering if anybody knows the reason why we cry when we are upset or in pain? From what I can see, the only benifit that arises is letting other members around you that something is wrong. However, in the process, you are loosing water a salts in the tears themselves?

So, random thought of the day... Is there any situation in which it would be beneficial to humans having a proboscis instead of (or additional to) our usual mouth parts?

I got into a discussion at work (fool me) with a person who turned out to be a IDer who unfortunately is also an aerospace engineer who went on about the evolution of the 4 bar link in the knee. he basically said that a 3 bar or a 2 bar link just won't work and it has to be a 4 bar link. Hence the ID bit ... Now my background is not in anatomy but rather biochem/molecular biocogy so I really don't have a particular idea on how the knee evolved .... Anyone know? To my irritation most of the google links point to ID sites

The Genome Project discovered that our DNA is 90% microbial and only 10% is ours. How did 90% get there if it is not done through HGT or LGT. Biologists state they do not see HGT in mutations by bacteria in our DNA. Another question is does a newborn baby also have 90% microbial DNA and if so how are they determined sterile at birth? We share 1% of our DNA with chimps. The remaining 9% is related to what other organisms?

Please correct me if I have this wrong is that mutations occur mostly through copying errors, transporons that move genes to different locations, environmental damage, viruses that change protein functions that through time eventually changes the appearance of life forms. I realize that HGT from microbial life is rare but I can't help thinking that it occurs more often that what is believed right now. Basically it is the microbial life that enable this planet to remain a living one. It is also believed that our cells originated from two different species of microbes. The chloroplast and the mitochondria was once an independent microbial life form. We are dependent o…

My existence today confirmed by this forum that my ancestry of Human, primates, etc all the way back to its origin is 100% true. This makes complete sense to me since any new organism from scratch after life became firmly established would have very little chance of survival. This information is extremely important for the masses to grasp its significance since we are pushing so many other species to extinction. They become a dead end and this stops evolution for all of them. Millions of years of evolution down the drain for all of the species that are currently on the extinction list and no hope of comeback. They can't because there is no place for them to live an…

It is apparently difficult for many of us to understand how evolution is actually defined. Please correct me if I am presenting the wrong assumption. Evolution is descent with modification (Life can only come from life) and nature never has to start from scratch again right? Is this the correct interpretation in a nutshell? I realize that there is several factors involved in this process. If true then the fact that I am here living right now, my ancestry goes back before I was classified as Human all the way back to the beginning of the first life on this planet. My line of descent would have many different names to describe who my ancestors were at any particula…