TerraForums Venus Flytrap, Nepenthes, Drosera and more talk
Register a free account today to become a member! Once signed in, you'll be able to participate on this site by adding your own topics and posts, as well as connect with other members through your own private inbox!
Worlds Most Rare Drosera
- Thread starter Tamlin Dawnstar
- Start date
There is an entire branch of plant science that also asks the same questions! In essence, this is what taxonomy and the related study of phyllogeny is about. It's a difficult question due to the length of time we are talking about: speciation is a process spanning millions of years. Fossil evidence is poor, and doesn't help much in answering this question, although recent advances in genetics makes it possible to gain some insight by comparing specific presence or absence of gene markers. Some questions will probably remain unanswered, such as did these species originate in one place in the world, or in multiple places at different times as a result of similar evolutionary mechanisms within specific plant families? If Drosera have a common ancestor, it is likely that such originated in Africa or Australia, and probably back when those continents were united. I believe that D. regia is the most "primitive" form within the genus although there are other primitive types as well in other continents: e.g. Drosera meristocaulis in Brasil. Other species like D. anglica and D. nidiformis are relative "newbies".
Yes,but sometimes large mutations can occur in a very short amount of time!,usualy brought about when there is a large change in enviromental factors eg.global warming,global cooling,nuceuler explosion etc.
Just look at how the dog has changed from its ancestor cannis lupus!
Some varietes of dog actually when crossed with a wolf will produce only sterile offspring! thus making them seperated by the species barier! In fact some scientists actualy place them in there own species ...c.famillaris!
I believe it was only several thousand years in the case of the dog.
There fore it doesnt necesarily take millions of years.
Just look at how the dog has changed from its ancestor cannis lupus!
Some varietes of dog actually when crossed with a wolf will produce only sterile offspring! thus making them seperated by the species barier! In fact some scientists actualy place them in there own species ...c.famillaris!
I believe it was only several thousand years in the case of the dog.
There fore it doesnt necesarily take millions of years.
>_< please don't compare animal and plant genetics, they function so very differently it's not fair... and I'm not even going to go into the K9 thing because there are too many conflicting views and it will just start another fight on the subject (but you should know that most K9's are starting to be reclassified as being the same species w/ different subspecies).
...However, you are very correct that speciation can occur quickly. In plants more so than in animals. This is because as soon as a plant's chromosome number increases evenly by poliploidation (is that a word?) or by single chromosomes doubling up, it is instantly a new species. You can start with a hybrid, or you can have a single species just double up. However, the new species may not be very different from the parent plant/plants. Usually polyploidy are bigger, and that’s about it. However, the sudden level of redundant data means mutations that would normally be lethal are compensated for thus leaving the DNA open for more change. DNA mutation occurs at a steady rate, but the number of non-lethal mutations will greatly increase meaning natural selection has more material to work with. Eventually, you can get the extra genes so distorted they won't recognize the original cross’s chromosomes. This means you have a population that has completely separated from the parent plants and no new accidents are going to make a new member of this species because they can't interbreed. Does that make sence?
Now here is how you get slower speciation. Same thing is happening, but remember these plants are all still very similar looking. It take several "technically" new species to show up before you can compare the end product back to the original and say, those are different plants at a glance. The more diverse the range of appearances, the further away from each other the groups have gone. Eventually transitional species die out and what you have left are a bunch of different but related species. AKA, what I believe Tamlin was referring to was the processes of creating dramatically different species adapted to a range of habitats with highly unique genes in addition to common roots way way way back.
Evolution can be fast, but the evolution of one part of a population while another stays the same or takes a different root is very slow.
Long term species diversity
1. isolate
2. mutate
3. disturbances/competition
Evolution of a species (This is your Domestic Dog, their genetic sequence is relatively unaltered, it is only the alleles that have changed. K9’s happen to have an incredibly adaptive set of DNA which is why so many phenotypes have arisen both in domestic and wild types. AKA they don’t NEED to become a new species to adapt to new environments… same for small cats. Gene Example: 1 gene determines snout shape and length in dogs. It’s an on-off switch that is timer based. The sooner it is turned off, the shorter and blockier the snout, the longer is it left on the longer and skinner and pointier the snout. 1 gene, big difference! This is also our variants of plants, a white vs. pink flower, fat vs. thin leaves etc.)
1. mutate
2. disturbances/competition
I luv genetics, sorry if I got boring there.
...However, you are very correct that speciation can occur quickly. In plants more so than in animals. This is because as soon as a plant's chromosome number increases evenly by poliploidation (is that a word?) or by single chromosomes doubling up, it is instantly a new species. You can start with a hybrid, or you can have a single species just double up. However, the new species may not be very different from the parent plant/plants. Usually polyploidy are bigger, and that’s about it. However, the sudden level of redundant data means mutations that would normally be lethal are compensated for thus leaving the DNA open for more change. DNA mutation occurs at a steady rate, but the number of non-lethal mutations will greatly increase meaning natural selection has more material to work with. Eventually, you can get the extra genes so distorted they won't recognize the original cross’s chromosomes. This means you have a population that has completely separated from the parent plants and no new accidents are going to make a new member of this species because they can't interbreed. Does that make sence?
Now here is how you get slower speciation. Same thing is happening, but remember these plants are all still very similar looking. It take several "technically" new species to show up before you can compare the end product back to the original and say, those are different plants at a glance. The more diverse the range of appearances, the further away from each other the groups have gone. Eventually transitional species die out and what you have left are a bunch of different but related species. AKA, what I believe Tamlin was referring to was the processes of creating dramatically different species adapted to a range of habitats with highly unique genes in addition to common roots way way way back.
Evolution can be fast, but the evolution of one part of a population while another stays the same or takes a different root is very slow.
Long term species diversity
1. isolate
2. mutate
3. disturbances/competition
Evolution of a species (This is your Domestic Dog, their genetic sequence is relatively unaltered, it is only the alleles that have changed. K9’s happen to have an incredibly adaptive set of DNA which is why so many phenotypes have arisen both in domestic and wild types. AKA they don’t NEED to become a new species to adapt to new environments… same for small cats. Gene Example: 1 gene determines snout shape and length in dogs. It’s an on-off switch that is timer based. The sooner it is turned off, the shorter and blockier the snout, the longer is it left on the longer and skinner and pointier the snout. 1 gene, big difference! This is also our variants of plants, a white vs. pink flower, fat vs. thin leaves etc.)
1. mutate
2. disturbances/competition
A very nice breakdown on the mechanics of speciation Darcie.
FYI "poliploidation" would be an incorrect term best covered by the use of "polyploidy" I think. Man, it's been quite a refresher course on genetics lately for me, lol.
Yes, genetic drift is a consequence of isolation. This is a very important consideration in speciation, but it is not until competition and natural selection operates on the new isolated populations that a final form becomes stable. Once the filial generations cannot recross back with the parent generation, species seggregation becomes much more definitive.
Despite the popularity of the X-men movies, mutation does not immediately grant species consideration, although it is an integral part of the process. A lot happens in 80 million years or so!
FYI "poliploidation" would be an incorrect term best covered by the use of "polyploidy" I think. Man, it's been quite a refresher course on genetics lately for me, lol.
Yes, genetic drift is a consequence of isolation. This is a very important consideration in speciation, but it is not until competition and natural selection operates on the new isolated populations that a final form becomes stable. Once the filial generations cannot recross back with the parent generation, species seggregation becomes much more definitive.
Despite the popularity of the X-men movies, mutation does not immediately grant species consideration, although it is an integral part of the process. A lot happens in 80 million years or so!
