Darwin's specimens, taxonomy & other matters

[Cath B]

Had a great day out today visiting Edinburgh Botanic Gardens (http://www.rbge.org.uk/) with a couple of friends.

This included a behind-the-scenes visit to the herbarium (http://www.rbge.org.uk/science/herbarium) to see just a few of the (almost) three million specimens, including Senecio darwinii collected by Darwin himself

http://apps.kew.org/herbcat/design/pictures/senecio-darwinii.jpg

http://apps.kew.org/herbcat/design/pictures/senecio-darwinii.jpg

(The picture is the more impressive Kew specimen)

All this made me think.

I am slightly acquainted with a few elderly amateur taxonomists. These folk are highly dedicated and meticulous and have provided a great deal of local information about, for example, what they refer to as sub species of blackberries and hawkweeds.

Yet I wonder if they are inclined to misinterpret their data.

It seems to me that they have a mindset which considers species to be "fixed", rather as Linnaeus would have thought rather than in a state of flux.

Thus, they speak of some wild flowers as hybrids when often I suspect that intermediary would be a more accurate description. Illustrated flora are also inclined to do this.

I'm thinking that genetic analysis will support the concept of intermediaries, but this is taking its time to filter through to interested amateurs.

Any thoughts anyone?

[nygreenguy]

Firstly, many dont know but Darwin was a fantastic botanist. Not just at identifying, but in the lab as well.

Sub-species tend to be looked at as ecotypes of the overall species. Those that fall just outside of what is normal.

After sub-species come variety, which has much more significant changes, but is still the same species. This can include dwarfed plants.

Hybrids have to do with the breeding of 2 separate species.

If they considered species to be fixed, they wouldnt use subgenus, they would use the normal species name.

As for hybrids, I dont understand your use of the term "intermediary". I mentioned what a hybrid is, and its really hard for there to be shades of grey to that. Either it is a hybrid, or it isnt.

Can you be more specific to your question?

[Cath B]

Sorry, sorry, sorry, I had a lot on my mind so didn't answer your post nygreenguy. This is the kind of thing I was getting at - (I'm still a bit too edgy to come up with my own phraseology right now.) I've bolded the pertinent stuff.

Meconopsis is a genus of flowering plants in the family Papaveraceae. The species have attractive flowers and have two distinct ranges. A single species, Meconopsis cambrica, also known as the Welsh poppy, is indigenous to England, Wales, Ireland, and the fringes of Western Europe. The other 40 or so (depending on classification) species are found in the Himalayas. Within the Himalayan types there is much debate as to what constitutes a particular species as many readily hybridise with each other and produce viable seed. It is likely that some individually-named species are in fact a single species but with an under-appreciated morphological diversity.

From http://en.wikipedia.org/wiki/Meconopsis

I wonder if similar stuff goes on in the UK wrt brambles, hawkweeds etc.

[nygreenguy]

The wiki article doesn't make sense. You can have viable seed and still be a separate species. To be the same species, the offspring must also be fertile, which id be willing to bet its not. It seems like the author doesn't understand the species concept.

[Cath B]

I suppose they may not have been studied thoroughly enough to determine whether or not they have fertile offspring.

It may be difficult to replicate appropriate growing conditions and therefore hard to demonstrate one way or the other.

[nygreenguy]

It may be difficult to replicate appropriate growing conditions and therefore hard to demonstrate one way or the other.

I doubt that. Here in upstate new york we grow tropical plants inside. Also, a third of their website is dedicated to propagating this flower!

I dont think this is something that the scientific community "somehow missed"

[Cath B]

If you reread my posts you will note that I did not refer to the "scientific community" (whatever that is) but to folk accustomed to differentiating species on the basis of morphology without considering the underlying genetics.

I wish I didn't get so wound up by the feeling I get (justified or otherwise) that your posts are dripping with scorn.

It makes it difficult for me to express myself coherently.

[nygreenguy]

If you reread my posts you will note that I did not refer to the "scientific community" (whatever that is) but to folk accustomed to differentiating species on the basis of morphology without considering the underlying genetics. Im sort of stuck in the middle of all this. I think too many people are all genetics or all morphology when its really a combo of the two.

I wish I didn't get so wound up by the feeling I get (justified or otherwise) that your posts are dripping with scorn. Sorry, its not directed at you but the people on the website and the wiki article and thats where the "scientific community" part came it. It pretty much all come from this statement: Within the Himalayan types there is much debate as to what constitutes a particular species as many readily hybridise with each other and produce viable seed. It is likely that some individually-named species are in fact a single species but with an under-appreciated morphological diversity.

Thats the statement that makes it seem like the scientific community somehow missed it when they dont even know what they are talking about!

It makes it difficult for me to express myself coherently. Im sorry! I dont me to seem harsh. Maybe its partially because ts finals week. At least im all done now!

[ck1]

Had a great day out today visiting Edinburgh Botanic Gardens (http://www.rbge.org.uk/) with a couple of friends.

This included a behind-the-scenes visit to the herbarium (http://www.rbge.org.uk/science/herbarium) to see just a few of the (almost) three million specimens, including Senecio darwinii collected by Darwin himself

http://apps.kew.org/herbcat/design/pictures/senecio-darwinii.jpg

http://apps.kew.org/herbcat/design/pictures/senecio-darwinii.jpg

(The picture is the more impressive Kew specimen)

All this made me think.

I am slightly acquainted with a few elderly amateur taxonomists. These folk are highly dedicated and meticulous and have provided a great deal of local information about, for example, what they refer to as sub species of blackberries and hawkweeds.

Yet I wonder if they are inclined to misinterpret their data.

It seems to me that they have a mindset which considers species to be "fixed", rather as Linnaeus would have thought rather than in a state of flux.

Thus, they speak of some wild flowers as hybrids when often I suspect that intermediary would be a more accurate description. Illustrated flora are also inclined to do this.

I'm thinking that genetic analysis will support the concept of intermediaries, but this is taking its time to filter through to interested amateurs.

Any thoughts anyone?

Tonight I saw a very nice NOVA special on flowers. It described the evolution of flowering plants, and showed some of the collections at Kew Gardens, including a specimen collected by Darwin.

It also said that flowers probably originated in China and showed lots of footage of the unbelievable diversity of flowering plants in this region of the world, along with fossils collected in that area of what may have been the first flowering plants.

Very interesting.

[BigEvil]

I just finished reading "The Brother Gardeners" by Andrea Wolf. It covers the men of botany during the 1700's (Bartram, Collinson, Lineas, and others). Quite fascinating, almost made me want to study plants.

[Cath B]

Tonight I saw a very nice NOVA special on flowers. It described the evolution of flowering plants, and showed some of the collections at Kew Gardens, including a specimen collected by Darwin.

It also said that flowers probably originated in China and showed lots of footage of the unbelievable diversity of flowering plants in this region of the world, along with fossils collected in that area of what may have been the first flowering plants.

Very interesting.

That does sound interesting!

I've been wondering a bit about the evolution of flowering plants myself.

We studied Carboniferous plant fossils when I was a student in the '70s but barely skimmed the surface of the evolution of flowering plants.

There are a lot of Carboniferous fossils around in the UK!

I remember taking my children to see an exhibition of Chinese dinosaurs round about the early 90s. There were many species previously unknown in the West. I'm guessing these plant finds are from a similar period.

[nygreenguy]

I think it is "The First Flower (http://www.pbs.org/wgbh/nova/flower/)".

The evolution of flowering plants is sort of tough because we believe they started out on mountains, but in those areas we dont really get much fossilization. For some time there was a debate is the first flower was a woody plant or herbaceous.

[ck1]

Tonight I saw a very nice NOVA special on flowers. It described the evolution of flowering plants, and showed some of the collections at Kew Gardens, including a specimen collected by Darwin.

It also said that flowers probably originated in China and showed lots of footage of the unbelievable diversity of flowering plants in this region of the world, along with fossils collected in that area of what may have been the first flowering plants.

Very interesting.

That does sound interesting!

I've been wondering a bit about the evolution of flowering plants myself.

We studied Carboniferous plant fossils when I was a student in the '70s but barely skimmed the surface of the evolution of flowering plants.

There are a lot of Carboniferous fossils around in the UK!

I remember taking my children to see an exhibition of Chinese dinosaurs round about the early 90s. There were many species previously unknown in the West. I'm guessing these plant finds are from a similar period.

Earlier this year I went to a Smithsonian exhibit on Darwin's orchids. Darwin spent a lot of time studying orchids and wrote a book on the subject. Before going I had no idea of the diversity of orchids and the amazing strategies they have evolved to facilitate pollination. Plus, they are gorgeous flowers.

[ck1]

I think it is "The First Flower (http://www.pbs.org/wgbh/nova/flower/)".

The evolution of flowering plants is sort of tough because we believe they started out on mountains, but in those areas we dont really get much fossilization. For some time there was a debate is the first flower was a woody plant or herbaceous.

The special focused largely on two scientists, one Chinese and one American, who were looking for fossilized flowers at a particular site. The Chinese scientist had found an interesting well preserved fossil whose structure suggested it was a precursor to modern flowers. I don't remember what they called it, but I do recall that there was some controversy about its date.

[SteveF]

This is a good book on plant evolution:

http://www.amazon.co.uk/Evolution-Plants-K-J-Willis/dp/0198500653/ref=sr_1_1?ie=UTF8&s=books&qid=1241617095&sr=8-1

[nygreenguy]

This is a good book on plant evolution:

http://www.amazon.co.uk/Evolution-Plants-K-J-Willis/dp/0198500653/ref=sr_1_1?ie=UTF8&s=books&qid=1241617095&sr=8-1

Checking THAT out today!

[nygreenguy]

The special focused largely on two scientists, one Chinese and one American, who were looking for fossilized flowers at a particular site. The Chinese scientist had found an interesting well preserved fossil whose structure suggested it was a precursor to modern flowers. I don't remember what they called it, but I do recall that there was some controversy about its date.

Archaefructus liaoningensis

Means first fruit

[SteveF]

This is a good book on plant evolution:

http://www.amazon.co.uk/Evolution-Plants-K-J-Willis/dp/0198500653/ref=sr_1_1?ie=UTF8&s=books&qid=1241617095&sr=8-1

Checking THAT out today!

I think you'll like it. Kathy Willis is a bit of a rolemodel of mine - she started out as a regular pollen analyst and has really branched out to do cool and interesting work.

[nygreenguy]

I think you'll like it. Kathy Willis is a bit of a rolemodel of mine - she started out as a regular pollen analyst and has really branched out to do cool and interesting work.

Hey now, I represent that remark! A "regular" pollen analyst? Branched out to do "cool and interesting" work?!?!

:mad:

[ck1]

The special focused largely on two scientists, one Chinese and one American, who were looking for fossilized flowers at a particular site. The Chinese scientist had found an interesting well preserved fossil whose structure suggested it was a precursor to modern flowers. I don't remember what they called it, but I do recall that there was some controversy about its date.

Archaefructus liaoningensis

Means first fruit

Thanks. Archaefructus. Trying to remember that all day!

[nygreenguy]

The special focused largely on two scientists, one Chinese and one American, who were looking for fossilized flowers at a particular site. The Chinese scientist had found an interesting well preserved fossil whose structure suggested it was a precursor to modern flowers. I don't remember what they called it, but I do recall that there was some controversy about its date.

Archaefructus liaoningensis

Means first fruit

Thanks. Archaefructus. Trying to remember that all day!

no. You can always check the nova site as well. They talk about it there! The latin/greek name makes so much sense its easy to remember!

[Valheru]

Hybridization isn't speciation, though. Offspring from white and black parents are going to yield a coffee-coloured "hybrid", if you will. The genetic "looseness" within a genome is what allows for variation within a species, when it's not really an intermediate, because you're dealing with mendelian genetics instead of macro-evolution.

[nygreenguy]

Hybridization isn't speciation, though. Offspring from white and black parents are going to yield a coffee-coloured "hybrid", Well, it depends on the species.


However, I think the point was that it produced a new species and NOT a hybrid. Except all they said was viable seed and not fertile offspring. If they had fertile offspring, then they would be a new species.

[Steviepinhead]

Hybridization isn't speciation, though. Offspring from white and black parents are going to yield a coffee-coloured "hybrid", if you will. The genetic "looseness" within a genome is what allows for variation within a species, when it's not really an intermediate, because you're dealing with mendelian genetics instead of macro-evolution.
There would certainly be a tendency for the offspring of light- and dark-skinned parents to fall in between her parents, in terms of skin tone. Particularly when averaged over enough parents, offspring, and generations... But it's not nearly predictable enough to make as definite statement as "are going to yield a coffee-colored 'hybrid.'" The various skin-tone genes do NOT produce a classic mendelian breakdown, sufficient to make predictions in individual cases.

Like the instances of "white" and "black" twins, for example.

[Valheru]

The technical veracity of my specific example aside, the point still stands firm, don't you agree?