Transitional Forms
I would like to know what a transistional form is?
If you go back nine generations in my family line you wouldnt consider them another species well what if you go back one hundred thousand generations back we would probably look alot different we would still be the same species go back another one hundred thousand generations and we would still be mammals and still the same species. Now go back a million generations from there and we are probably some kind of reptile but we are still the same species. This is why the term "kind" doesnt make any since, but the term species doesnt make any since. Whats with all the hominds, erectus, sapien, egaster etc. Wouldnt my grandparents have there on name as well or my great grand children, what will we be called one thousand generations from now I imagine human.
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You are one of the transitional forms between your great grand parants and your great grandchildren. What kind of changes can you expect from a process that takes 10,000 generations to make dramatic changes?
"Very funny Scotty; now beam down our clothes."
VEGETARIAN: Ancient Hindu word for "lousy hunter"
If man was formed from dirt, why is there still dirt?
"Transitional form" was a term used by scientists in the late 1800's, early 1900's. Darwin's theory was still new, they didn't know about DNA (though they had some ideas about simple genetics), and they hadn't found many fossils yet.
Now, the museums and paleontology laboratories are filled with thousands of fossils, we have a pretty good idea of what is going on with genetics and DNA, and Darwin's theory has been tested and supported by other sciences. So scientists today don't use the term as it doesn't make much sense.
The term "transitional form" is used nowadays by creationists. Supposedly there aren't any transitional forms. The difficulty is, not only is this over simplified, it is also a very narrow view of evolution. Evolution is messy. Just like living species are messy. Sometimes we have enough fossils that we can make a pretty graph, sometimes there aren't enough. But is a particular fossil a transitional species or an outlier? We can't always tell. So we do genetic analysis - that gives us a better picture of relatedness in modern species and then we can go back and re-examine the fossils we have and make better conclusions about relatedness.
Technically, when you look in a mirror, you are looking at a transitional species. All species are in transition - either to a similar species or a new species or to extinction.
If you want lots of pictures of transitional forms - lots and lots - check out Donald R Prothero's book from the library, Evolution: What the Fossils Say and Why it Matters. He is a working paleontologist and specializes in mammals that evolved in North America. His book has all kinds of fossils, including humans, and it is easy to read, and he is careful to explain what "transitional" means to a modern scientist.
-- I feel so much better since I stopped trying to believe.
"We are entitled to our own opinions. We're not entitled to our own facts"- Al Franken
"If death isn't sweet oblivion, I will be severely disappointed" - Ruth M.
You didnt explain what species is im thinking there is no such thing as species. What about the hominds I mentioned why do they have different names that would mean that every single new person born would be its own species
Very briefly - a species is a population that is reproductively isolated from other populations.
You can force lions and tigers to interbreed - but they do not and will not in the wild. Polar bears and brown bears used to be separate species in that they could interbreed and did not have an opportunity. Because of the massive ice melt in the Arctic, they have found obvious cross bred bears. Many song birds are separated by their mating songs. I saw a program once where they measured the birds hearing - same test they use to see if a human is deaf, just sized for the bird. The test measures the response of the muscle in the ear. The birds did NOT hear mating songs that were of another species. They DID hear the song of their own species.
That is amazing - they have evolved so that the physical muscles of their ears do not respond to any mating song but their own population. Doesn't matter whether they could have fertile offspring or not - because the females of the other species wouldn't know the male was nearby to mate with because she literally could not hear him.
It doesn't have to be a physical difference, a genetic difference, an environmental difference - the two groups just don't mix "socially". So humans can and do mate with other humans who are from halfway around the world, have different skin, hair, eye color, are different sizes, and so on and so forth. Doesn't matter if you or I do. All that matters is that some people do - and that is enough to keep us all one species.
-- I feel so much better since I stopped trying to believe.
"We are entitled to our own opinions. We're not entitled to our own facts"- Al Franken
"If death isn't sweet oblivion, I will be severely disappointed" - Ruth M.
Youre not explaining all the names for the hominids though.
How can they only hear a certain song (dont you mean frequency range and even that doesnt make since)thats like saying you can only hear rap music and I can only hear rock?
is a Poe but my suspicious mind wonders. You expect some answers to stick.
There are excellent precis of the nature of evolution on the internet, ymalm. I recommend the vigorous application of Google. In short, creatures that can breed are the same species. Creatures that can't are another species. A genetic switch divides species. New research suggest this switch is simpler than first thought.
Species that are genetically isolated drift apart over time as they adapt to new environments or their environments change. It's not always the case. Some creatures work so well they don't change much at all. The hominid names are labels given to bones and fossils of extinct human species - some recent we could breed with and have genetic remnants of - like Neanderthal (all modern Europeans are 4-8 per cent Nthal). Other species are far older. Back to 4 million years or so.
Throughout this time all these species were in transition. The fossils are like snapshots in time and we label these fossils as such and such a species for reference. If there were more fossil snapshots there would be more species known. Fossils are glimpses of the momentary state of forms in constant transition. They must obviously be called something.
You need to stop thinking laterally. Think of time as a sea and 'now' as the surface of that sea. Think of species as islands in an archipelago of life. The islands are not connected on the surface but by undersea mountain chains of shared genetic information lying beneath the surface of time. Although now separated, all these species islands are ultimately connected to each other and to the 'earth' (genetic node zero) if you go deep enough/far enough back.
"Experiments are the only means of knowledge at our disposal. The rest is poetry, imagination." Max Planck
Also everting you said makes sense you could probably make a computer program that functions that way but when I start thinking about all the different animals it gets really weird but I understand completely the evolutionary tree and genetic drift
A species is a population that can naturally interbreed. You wouldn't be able to breed with a reptile, so you wouldn't be the same species.
I'm not sure what you mean. There's a lot of names because we like to put things into groups.
Again, not sure what you mean. Don't confuse the label with reality. You can call your descendant one million generations from now "human," but that doesn't mean you'll necessarily be able to interbreed.
Our revels now are ended. These our actors, | As I foretold you, were all spirits, and | Are melted into air, into thin air; | And, like the baseless fabric of this vision, | The cloud-capped towers, the gorgeous palaces, | The solemn temples, the great globe itself, - Yea, all which it inherit, shall dissolve, | And, like this insubstantial pageant faded, | Leave not a rack behind. We are such stuff | As dreams are made on, and our little life | Is rounded with a sleep. - Shakespeare
No offense taken. We have people come around arguing by question sometimes, is all. You ask a lot of questions about a very specific and difficult area that's often used by theists to attempt to refute evolutionary theory. "Where are all the transitional forms, species are distinct, there's only micro but not macro evolution, missing links and so on and so forth."
The questions you are asking take books and books to answer and it's difficult to address these issues with the broad brush strokes employed chatting here.My advice is to stick around and ask lots of questions.
A creature might be driven onto land by predators or a food supply or a genetic mutation that allows it to exploit a new niche. Alternatively and more likely, it might die out completely. Animals isolated on islands shrink. Plate tectonics moves species into new climates.
Can anyone suggest some good books on evolution? I have Stephen Jay Gould's Evolutionary Theory but it's more than 1000 pages long and probably more torturous than part 2 and 3 of Lord of the Rings.
You don't conform to Poe's Law anyway - I tend to incorrectly use the term to refer to theistic Q ships. It's not an offensive term. Poe's Law describes some one who is furiously pretending to be a theist yet is virtually indistinguishable from a real theist because theism itself is so silly. That's obviously not you.
"Experiments are the only means of knowledge at our disposal. The rest is poetry, imagination." Max Planck
Why hasnt a time lapse video been done on natural selection to show it taking place im sure an advanced computer can do this?
You know when christians say you have to have the holy spirit to understand the scriptures, this is obvioulsy a cop put since they dont understand it either they are basically saying they just believe and feel that its true.But ive noticed that relgious people who argue with evolution supporters(evolutionist sounds silly) they say you ovisouly dont understand it so you cant say anything on the subject if this is the case(which is why im asking questions) then they shouldnt be surprised at the people who dont accept it, you basically have to be compelled to want to learn about it. Like people say the earth is billions of years old and people who disagree arent taking seriously like as far as i am concerned its only as old as what I can trust about history and whats been pasted down so how do you conclude that the earth is as old as it is and say dinosaurs went extinct 65 million years ago?
Like potassium argon allow dating back 4 billion years by measuring the decay of radioactive isotopes. Samarium 147 has a half life of 100 billion years and is used to date meteorites older than the earth. These dating techniques are not based on faith but on proven methods.
"Experiments are the only means of knowledge at our disposal. The rest is poetry, imagination." Max Planck
How do they know that it has a half life of a million years if you cant live that long to know?
Also I think if i found my own fossils I would be more convinced. What is this geological column I hear about and where can I see with my own eyes?
You patiently observe the decay over a short period, say a day or two; measure the decay; then continue to observe to see if the same amount of decay occures over the same time period. This is called a 'consistent rate of decay' it may take months or years to establish the consisent rate of decay; this is where the patience comes in. Once the rate [ratio] is established it is simple math to calculate the half-life.
"Very funny Scotty; now beam down our clothes."
VEGETARIAN: Ancient Hindu word for "lousy hunter"
If man was formed from dirt, why is there still dirt?
Looking at the canyon, even in photographs, or a similer place, will show you layer ontop of layer [ called strata] of rock. Checking the minerals found in each layer for their half-life decay will tell a geologist exactly how old the layer is [give or take a few hundred years]. Digging a hole in your backyard will also show you strata but not has dramaticly has the grand canyon.
"Very funny Scotty; now beam down our clothes."
VEGETARIAN: Ancient Hindu word for "lousy hunter"
If man was formed from dirt, why is there still dirt?
Shouldnt the the geological column exist on every inch of the planet its not like the grand canyon is older than my back yard right?
Looking at canyons just saves you from turning your back yard into a dig site.
"I do this real moron thing, and it's called thinking. And apparently I'm not a very good American because I like to form my own opinions."
— George Carlin
Thats all I wanted to know.
So are there possible fossils in my backyard if I dig far enough?
Yes and no. It depends on what kind of rocks you have locally. You will only find fossils in sedimentary rocks.
That being said, you don't really have to go to the grand canyon. Look around where you live and you may find a place where there has been some excavation as where they cut through a hill or ridge to make a road. If there are sedimentary rocks there, you will at least see the layering of the rocks. If you can get permission from the owner to take rocks off site, you might just find some fossils.
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It might be better to back this up a bit to consider some rather more basic material. Really, how do we know the age of anything?
Well, if you have ever cut a tree down, you will have seen the growth rings. From those, you can count back the age of the tree as one ring per year. You will also notice that there are often variations in the color and thickness of the rings. Here is where things get interesting.
If you cut down a few trees in the same general area, you will see that the ring variations show a general pattern. Basically, they are caused by changes in the local environment. Wet years, dry years, years following a forest fire and so on all play a role in how the trees grow from year to year.
Now, you might tend to think that that can only take you as far back as the age of the local forest. That would only be slightly accurate. If you can find old buildings, you can figure out when they were built by matching up the rings in the wood they were built from. There are some places where the tree ring dates have been used to build up a consistent calendar going back several thousand years. Fence posts tend to be really good for this as they are usually made from the most durable types of wood.
Past that, it is possible to go back even farther by dating the layers of sediment in the banks of rivers and lakes. Again, you generally get one layer per year, although there is a bit more variation than with tree rings. When you go deep enough, the pressure and heat on the layers are what cause the formation from the layers of sedimentary rocks. Since things die and sometimes fall in the water, this is primarily where fossils form.
By using a few different methods that I will get to presently, we can just keep on dating the layers further down. That is what is actually meant by the geological column.
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I'm with Atheistextremist on this one, this guy is a Poe. His spelling and sentence structure is poor, but inconsistently so.
So ymalmsteen887, what is your current position on evolution? I thought I noticed a "we can't be sure evolution happened because nobody was around to see it happen" attitude. Also, what is your current belief system? Do you believe in the God of the Bible?
"Don't seek these laws to understand. Only the mad can comprehend..." -- George Cosbuc
I disagree. I think he's honestly confused about all this.
Our revels now are ended. These our actors, | As I foretold you, were all spirits, and | Are melted into air, into thin air; | And, like the baseless fabric of this vision, | The cloud-capped towers, the gorgeous palaces, | The solemn temples, the great globe itself, - Yea, all which it inherit, shall dissolve, | And, like this insubstantial pageant faded, | Leave not a rack behind. We are such stuff | As dreams are made on, and our little life | Is rounded with a sleep. - Shakespeare
I believe Evolution is true and no christianity is a force for evil that should have been eradicated a long time ago.
I've been wrong before![Smiling Smiling](/modules/smileys/examples/001.gif)
"Don't seek these laws to understand. Only the mad can comprehend..." -- George Cosbuc