I have no idea. 
It’s just that it’s always struck me in these threads vis-a-vis evolution that no one ever seems to talk about plant life and/or how it’s evolved.
Oh! Yeah, I’ve noticed that too. Makes me think of Ellie in Jurassic Park, pointing out that plants have defenses and modes of attack and communication (through chemicals released in the soil or air, I’m not being woo-woo here) all of their own, and seeing growing formerly extinct plants blows her mind, but all anyone wants to talk about is the freakin’ dinosaurs! 
Many people have observed similarities between chlorophyll and hemoglobin and hypthesized that the similarities are due to plants and animals having a common ancestor.
Do plants have DNA and base pair coding similar to that of animals? I think so. If so, it again suggests a common ancestor.
I would not, 3.8 billions years ago there was more energy and building blocks around to start life.
Add to that a world that was radioactive (a power source that I think it is mostly ignored when attempting to recreate conditions to test for possible origins of life) and with volcanoes and water coming in. Taking all that into account it would seem to me that life would not lose a chance to appear then.
Microscopic life that is, because only after the planet cooled down was that then multicellular organisms could develop.
Yes and yes.
BTW, that classic National Geographic article had a great intro, the cover of the magazine asked:
**
Was Darwin wrong?**
I opened the magazine with the fear that some creationists had gotten a hand of the editorial board of the magazine and it was going to be a sickening “let us give a chance to the other side.” kind of article.
The answer in page 3:
NO
In an even bigger font size.
Why are you assuming all changes are small? Remember that girl in India who was born with four arms, not long ago? That’s a quantum leap over all her two-armed ancestors. If she had been allowed to mature with those arms, perhaps they would have become an evolutionary advantage. I can think of lots of circumstances in which we’d be better off with an additional arm or two. This could have been an example of evolution at work, in only one generation.
Combusting? Dude: it’s prokaryotes, not pyrokinetics!
I think you need to define “small.” Quite possibly, only a small genetic change will cause somebody to grow an extra pair of arms.
Remember, genes are more like a recipe than a blueprint.
Ah, the discredited hopeful monster theory. First, as I recall that was an example of partially merged twins; not something genetic and inheritable. Second, such drastic alterations are pretty much universally unhealthy, or fatal. And third, such large alterations make finding a mate much, much harder. It’s barely possible that at one point or another, such drastic alterations actually did result in an evolutionary leap. But even if it happened, that would be a vanishingly rare freak occurrence; not a significant driver of evolution.
As long as you don’t assume the change has to be advantageous at the time it develops, for the reason it ends up being selected for eventually, yes, they can. Also noting that big physical changes sometimes arise from small genetic ones. See “preselection”, “homeobox genes” and Dawkins’ wonderful Climbing Mount Improbable.
I don’t know about this (or at least I don’t understand it).
The only way to have millions upon millions of dice throws at once is to have millions upon millions of dice all at once. It seems that in the early days of this thing called life there were significantly fewer dice available.
Either there was some sequential evolution which branched fairly quickly into variated species and forms (animals and plants) or there was a spontanious event that caused similar building blocks to form in millions of ways up front that then took billions upon billions of dice throws to get to where we are today.
[wittnessing alert]* Kind of like a big Dungeon Master with a platnum AMEX shopping at the Cosmic Comic Carnival and loading up on a million different Dragon Dice. [/wittnessing alert]
*At least I’m man enough to admit it.
Even if there are few species (or even only one), there’s still a large number of individuals.
Sure, except that wouldn’t last for long. I haven’t gotten to this lab in BIO class yet, but apparently we’re going to grow bacteria - simple prokaryotic cells similar to the “first life” cells. They multiply by dividing, and they do it very quickly - sometimes in only a few hours. So, since 1 becomes 2 and 2 become 4 and 4 become 8, it only takes 20 generations before we have over 1 million (1,048,576, to be precise) “dice” to throw around. And 2 million in the next generation, and then 4 million! Et cetera. Even if we assume that half of those offspring don’t survive, we can have 1 billion dice in less than a week.
Even if there are few species (or even only one), there’s still a large number of individuals. As soon as one organism arises, it will fill every square inche fits for survival in no time, givern the rate of “reproduction” of such simple organisms. Even more so since it doesn’t have any competition. After only one year, there will be billions or copies of it all around the place, and some of them will probably already have mutated.
The only gap is no life/life. Once there’s life, all bets are off.
Assuming 50% of the offspring are viable the number reaches 1 million in 21 generations. At 10% viability it hits 1 million in 24 generations and 1 billion in 34 generations. Also assuming an 8 hour cycle for such a simple life form these would hit 34 generations in 272 hours, a little over 11 days.
Assuming humans have an average of 25 years per generation (a blind number, quite high and quite conservative), and an adjusted procreation rate of 33% due to sexual vs. asexual reproduction, we would theoretically reach the 1 billion mark (technically 1,288,490,189) in 32 generations or in about 800 years at 100% viability or 900 years at 10% viability (war, plague, pestilance, genocide and people who just can’t get a date).
This is also assuming a reproduction rate of 1 child per 2 adults. I think that’s somewhere around 2.7 these days but I don’t know for sure. This is a worse case scenario anyway.
So, from one person to one billion people in less than a thousand years. My math machine does not want to work out how many people there would be in the 5000 some odd years of written history let alone the tens of thousands of years of archeological history, even with a low average life span the number would be huge. Either that or the viability rate of the species would be very low, I would guess under 1% but that’s just off the top of my head.
And that’s just one species with a fairly short history compaired to the full archeological spectrum, a blip on the screen so to speak. Add to that the other millions of species that have shared the planet since the point that there were at least a million different species around. All of this times the billions of years since life began (adjusted for catastrophy of course: volcanos, tsunamis, rogue asteroids, Dave’s Insanity Sauce, etc…).
The numbers don’t add up to me. It seems as if, without some serious coordination we would be stepping on organisms with each foot fall (ok, we are stepping on some organisms with each foot fall, and breathing in hundereds with each breath, but the scale I’m talking about is larger than that, we’d be tripping over billions of fairly complex organisms).
I’m not personally attacking evolution or currently advocating creationism. I’m just wondering if I have the math somewhat close and, if so, as the original question stands - Is evolution enough to explain the diversity of life (and the seemingly infinite complexity of the full organic system without some direction)?
You probably want to start with 2 people. 
Your math fails to account for competition for resources. These numbers a self-limiting when you end up with limited food and space resources. Populations don’t expand that quickly because some other species (or just members of the species in question) are already in that niche or are in competition for resources.
But niches fill up and there are plenty of organisms for evolution to operate on.
There is something here that I see but have a hard time explaining, so I ask for your patience.
There are about 6 billion humans on Earth right now. Each of us had 2 parents, each of them had 2 parents, etc. Within a very short space of time each of us has more ancestors than humans ever alive: so we all share those ancestors pretty quickly, do we not?
I’m not sure what I’m driving at, actually. It just seems really important to me. Once we were a very small population, and it would appear that since that time we have not “evolved”. We are them, they are us.
Is it derailing the thread to speculate what “evolution” might occur in humans? How? When?
Also, somewhere I remember reading (could have been something by Carl Sagan) that humans share DNA with Petunias. I think this was in a discussion about Mr. Spock being the impossible offspring of a Vulcan and a Human.
There is strong evidence that we (ie, our ancestors) went through a genetic bottleneck around 60k years ago, and there may have been as few as 10,000 humans total at that time. This would have been right before the time that some of our ancestors left Africa and colonized Asia, Australia, Europe and the Americas.
Just by looking at the various ethnic groups you see around the world, it’s pretty obvious that we’ve evolved some since that time.
Every population is always evolving. Whether that evolution is visible to the casual observer is a different issue. Every new generation is new mix of the genes from the past generation, plus a few mutations. Sometimes those mutations are harmful, sometimes beneficial and sometimes neutral. It all depends on the the conditions in the environment at the time.
Yes, we share genes with all living organisms on earth. Link. How you define what % we share can vary depending on what you are comparing, but it’s pretty surprising how closely we are related to something like a mouse (about 90% shared DNA).
I don’t see the various ethnic groups as “evolution”. Am I wrong?
Does the Black Death mean anything to you at all? Until fairly recently (the last few hundred years) disease and famine pruned the population quite nicely. The same for animals. More prey, more predators.
I’m not sure what infant mortality rates were, and I’m too lazy to look them up, but the reason that many cultures didn’t name babies until a week after birth was that so many of them died.
First of, no processor is that fast (yet.) You’re probably confusing clocks with instructions for the first part.
Second, the reason it can process so much is that it has two cores. Life has the equivalent of billions and billions of processors - the more primitive the life, the more reproduction and the more chance for mutation. So you should reconsider the case with a billion core processor.
Third, you should read about how much genetic information we share with our ancestors and cousins. The number of changes is not all that great.
Remember, life is a bush. You don’t need that much branching at each stage to get a lot of diversity at the end.