Evolution, Morphology and Exobiology

"Furthermore evolution will push very hard not to get excluded of selection entirely. ". I heard this statement many times, yet i find no mathematical basis for it. For example - If for example mutation allows you to increase your successful offspring from 7 to 8, how come its inferior to mutation that increase it from 0 to 1? Anyway if this is true, does it mean that in declining fertility rates - selection pressure increases , because for more and more members of the population it becomes matter of whether to have 0 or 1, not 7 or 8. Does it differ in tournament and monogamous species? Lastly i want to transfer humans. In countries and societies where the fertility …

Hi, I just wanted to know If we did measure and observe this things in evolution: 1) Loss of information in the genes such as devolving traits. 2) Gain of information in the genes such a developing new traits. (Could be the Lenski Experiment be an example of this?) 3) All the mentioned above was observed at a macro scale such as fossils, genes, embryology, etc?

I know science is more geared towards answering the "how" questions instead of the "why" questions, but why do living things even survive in the first place? Why do they perform homeostasis? Why don't they just die? Presumably, the first living organisms were just a bunch of chemical reactions contained within a semi-permeable membrane. If the microorganisms couldn't withstand the heat or the cold, it was "unfit" and died. Got it. But for the more "advanced" organisms, what purpose does survival even have? Why does a conscious entity, aware of its surroundings and even possibly of itself, want to continue to live and reproduce? Organisms all react to their env…

Evolution can be an intimidating topic to start learning about. Not just because of its implications, but also because of its complexity and magnitude. I think the best way to introduce the subject to the uninitiated is through short videos that provide an overview of evolution's fundamental principles. There's a lot out there, but here is my submission. It's the book Why Evolution is True by Biologist Jerry Coyne transposed into a "Videobook": video removed due to possible copyright violations What are your favorite videos on Evolution?

I just finished a project I've been contemplating for quite some time. Its a simple program with little creatures that evolve over time and I've been able to evolve a few interesting creatures. Things that evade other creatures, find food, avoid walls etc, however it takes time. Not quite as much time as real world evolution but enough to make me wish there were a few more instances of the program running. I was wondering if anyone with some knowledge of actual evolutionary processes wanted to give it a try and some feedback? The software can be found here: www.lexicon-labs.com Thanks!

Hello, I am a high school student starting my junior year in the fall. I will be taking AP Biology, and would like to have a somewhat better understanding of evolution before I start. I've been meaning to read up on evolution for a while, but I've been timid because I don't want to find that I've built my understanding around information that is incorrect or already outdated. I want to ask about The Greatest Show on Earth in particular, since I have already read a few chapters of it, and like the style; should I be worried because it came out in 2009? Does the six year gap matter much for people who aren't scientists? If Show is outdated, what are some newer books that wo…

Hi everyone! I'm new here and I don't have any idea if it is the right forum part in which I write my question - so sorry for that. At the moment I'm working on my master degree and now I'm collecting the literature... So my problem is, I was doing the testing of a vaccine in mice and I detected different antibodies. Especially subtypes of IgG. Can you tell me first when do IgG2a, IgG2b and IgG2c appear? (I know that this is also dependent from the animal model one uses.) And secondly, what are they function so what does it mean, if there would be for example a lot of IgG2b? Thank you very much for you answers! Greets

Simply My question is how instinct happens.. or what is the origin of instinct ??

Hello! I was wondering if anyone was interested in helping me calculate the probability of being alive as a human. In other words, the probability of you or I being here. For example to start things off it was a one in 300 million (on average) chance that the combination of the sperm and egg involved in your conception grew into you. However most couples attempt to conceive several times until they are successful and may have several kids. So the first thing we need is the chance of you arising from any two people based on the current population (or the population at your birth). We then need a probability of your parents meeting based on the population and in…

Here is a Pastor's comment. Can someone refute this please! "Can't help but to quote former President Ronald Reagan during one of his presidential debates after watching this news clip and hearing the criticisms from 'some' scientists about 'Jurassic World ' - President Reagan's great comeback, "There you go again!" Really ... to 'some' scientists, ALL dinosaurs would have had feathers? How come we have so few examples in the entire fossil record - wait a minute - ONE example - archeopteryx. Furthermore, check out this link about another great hoax dealing with alleged fossils supporting the feather myth - https://www.youtube.com/watch?v=1Iz7GResDtQ Yep, I've said e…

I may be incorrectly extracting information from this analysis but, according to the study: " in our more refined analysis, there was no relationship between periods of accelerated change (i.e. large brain residuals) and increased climate variability over 100 ky time-blocks, contrary to what would be expected from Potts' variability selection hypothesis. Nor is there consistent evidence at the super-species level to support either the variability selection or the aridity hypotheses using sea-level indicators . Furthermore, when we use aeolian dust records, which provide a continental indicator for both aridity and variability, we do not find consistent evidence to suppo…

1- are the micro & macro evolution the same ? does the creationists accepted micro evolution ? 2- is there an examples for natural selection ? 3- how can the wheels evolve from ground species?.. David Berlinski says it needs about 50 000 amendment.. so could that happened? 4-is the mutations based what the organism wants.. I mean, for example, there is light .. How can the organism make an organ that be effected by light ?

Hi everyone, I have a general question-ish/ proposition, but more or less I would like this thread to serve as a sort of disorganized compendium of thoughts related to specific questions of what I want to call evolutionary plasticity. What I mean by evolutionary plasticity is basically an account of the differences in evolutionary histories (speed of evolution, outcomes, influences) of whatever lineage you may imagine. I'm interested in what drives evolution, and how these different driving forces may alter the outcome of a particular situation. My question is sort of a long-winded one, and it's difficult for me to ask without giving some back-story first. I…

I have made a theory so if this can't go here please tell me I've been doing research on Evolution I theorize that there will be a point when species become perfect for their environment, I believe Humans are close to this I have done research on Natural Selection and I believe we may see a world where humans are perfectly adapted for the environment so much we can not evolve any more because we already have what we need. Now yes I do see the flaws in which how the weak die the strong live but now we have medicine and technology so now the weak and the strong live so this comes that if evolution make a species as intelligent as us it is possible we could reach a peak th…

I've read much psychological discussion on Dr Badcocks blog on PsychologyToday. However, given that Badcock and Crespi's imprinted brain theory recently recieved some strong support (below), I would like to know more about the theory's biological underpinnings. Opposite risk patterns for autism and schizophrenia are associated with normal variation in birth size: phenotypic support for hypothesized diametric gene-dosage effects. What are imprinted genes? How could they make such general inferences about paternal-maternal baises in gene expression or silencing?

As near as I can figure, gene regulatory networks and epigenetic mechanisms both regulate when and were and to what extent genes get expressed. But what is the relationship between GRNs and epigenetics? Are epigenetic mechanisms a subset of GRNs? If so, what distinguishes epigenetic mechanisms from other aspect of GRNs? Or are GRNs and epigenetic mechanisms distinct cellular mechanisms that work in tandem? Any clarification regarding these terms will be appreciated!

Hi- I'm new to this group but I have an interesting question posed by a friend. I know that some organisms reproduce asexually (like slime mold), and some organisms can flip between male and female (like fish), but among organisms that reproduce sexually, why did they evolve into just two distinctive groups--male and female--and not many different groups. Thanks in advance!

So recently, I came across this video called "The Greatest Lie Ever Told" on Youtube. Now the video starts off about how evolution is a tactic in creating a religion for the NWO and a bunch of things of that sort. It does take a while for him to stop talking about his idea that the theory of evolution is a religion and a part of the NWO, but his claims against evolution start at around 10 minutes in. And that's where I need your help, particularly people who have studied evolution immensely. I'm in high school, I support evolution, but I only have a vague idea about evolution as opposed to someone who has studied it for years. So I can't fully rebut what he is saying or e…

A friend of mine showed me this wood roach just now that she acquired from a prac that was leading. When she first saw it, she says that it was in appearance, but since having been in a falcon tube in her pocket for 3 hours (it came out of a white bucket), it had changed colour from white to a light brown. Is this the result of temperature or something else? I thought maybe it was a response to light, but the bucket it was in was dark. Edit: this is a picture of the little guy now.

Hello, just been doing some research and trying to find some answers. I've been reading that more complex life tend to be found in the higher layers of the fossil record and more simplistic life tend to be in lower layers. However, I've been trying to find what makes one form of life more complex than another. Is it chromosome count? Being a multicellular organism? Asexual vs sexual reproduction? Consciousness and higher brain functions? I don't think a high number of chromosomes alone makes one form complex since some single celled organisms have exponentially more chromosomes than humans. Still, it seems odd that while humans possess a type of consciousness this…

Now I'd like to move the discussion on fire use by hominds further from its earliest incarnations: http://www.scienceforums.net/topic/85193-early-use-of-fire-by-hominds/to a time where fire creation and use had become commonplace. Let's say we're a H. erectus specimen living around the fertile crescent region of the Middle East circa .7myr BP. We would living in a sort of tropical climate, with cool grasslands and sparse woodlands. Now the question becomes: which of the various methods of starting fires would be tmost likely to be in use? I'd like to think of flint and iron since stone tools had been used and struck for so much time by then, that I find it simple to …

I decided to split this from this thread, where the OP provided this interesting case study. Paternal Inheritance of Mitochondrial DNA (Schwartz and Vissing, 2002) http://www.nejm.org/doi/pdf/10.1056/NEJMoa020350 A biparentally heritable strain of mitochondria might be more fit. What if biparental strains take hold from time to time only to negate themselves after they've succeeded, causing the population to revert to the maternal mode of inheritance? Has this possibility been investigated? I know little about the analysis of the maternal line via mtDNA. My thoughts are this. If such strains are allowed to appear, either they harm the organism too much to…

" In fact all animal species have evolved from the stage where there were no distinct male and female, and the reproduction was asexual. Sexual drive was present even then – apparently because it serves an important biological purpose. E.g. strong sexual drive is found amongst species that have not yet achieved sexual dimorphism. There are either only females or a hermaphrodite being, but sex still takes place throughout the year --- unlike in male-female sex which is only when procreation is required. Thus sexual drive precedes sexual dimorphism. These are clear evidences that nature chose sex as a means to reproduce by either diverting a small part of sexual urge (alr…

¿? -- Is it wrong to say... - By nature, animals and we humans store energy in times of bonanza to help ensure survival in times of scarcity and that process is embedded in genetics. It happens when there is abundance of food, bellies grow and life can be sustained longer. - Health professionals and science assures being overweight shortens lives. * How come these are in straight collision paths ? Nature promoting at the same time survival and earlier death ? Is there a gene fault to immediately get rid of stored fat in times food intake becomes plentiful ? *Seems true, you do not see fat people in their seventies and eigthies. Fat ones are already dea…

Hi, How does the evolution of plants happen?, such as how did some plants/trees/etc come about? And in your opinion do you think nature will evovle more?