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Post by neuropteris on Jan 13, 2007 10:11:33 GMT -5
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Post by neuropteris on Jan 13, 2007 10:13:54 GMT -5
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Post by Joe Botting on Jan 14, 2007 8:37:59 GMT -5
Hi Andy. Wow. Those are absolutely gorgeous, and the photography is wonderful as well. I really love the Eusphenopteris (If I had to pick one, but it might just as well have been almost any of them!). Honestly, who needs museums when we have galleries like this?  Despite not knowing much about Carboniferous plants, I'm always amazed by how rarely I come across a new one. I was wondering if this is because the diversity is actually extremely low, compared with modern tropical forests, or if it's more about how few species are common enough to be found well enough preserved to describe them... Do you know if anyone has actually described the plant ecology of these forests? Or do you regularly find leaves that you can't identify? In invertebrates, because of the hollow curve distribution where the majority of species are rare, there is a very good chance of finding a rare one because their diversity is so great. I get the impression the distribution pattern here is a bit different - but am I completely wrong? Many thanks for posting the wonderful photos! Joe |
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Post by Joe Botting on Jan 14, 2007 8:39:21 GMT -5
p.s. Commiserations on the loss of the exposure! It must be soul-destrying to see a place like that filled in...  |
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Post by neuropteris on Jan 15, 2007 15:32:27 GMT -5
Hi Joe - glad you liked them There do seem to be a few common genera of upper carb (I believe I'm supposed to call it the Pennsylvanian now) plants that are found throughout the period eg Pecopteris, Neuropteris, Alethopteris etc are found at Westphalian A sites such as this and also up in the Westphalian D like Mazon creek although the % of occurence and exact species do vary. You've got to remember though that there can be dozens of different species within each of these genera based on pinnule size and shape and veination pattern and several different species of the same genus can exist together at the same site. Other species are more restricted and are only found at certain horizons. Also many named types are merely fragments of much larger plants eg Stigmaria, Lepidodendron, Lepidostrobus, Lepidostrobophyllum, Lycopodites and Cyperites are all parts of the same organism. Coal forest ecology has been looked at and there are many papers eg The Ecology of Coal Measures floras from Northern Britain Proceedings of the Geologists Association 90 97-116 1979. Christopher Cleals and Barry Thomas's Plant Fossils of the British Coal Measures published by the Palaeontological Association contains an overview and has many references- most of which I've still got to try and get hold of yet! I do come across oddities sometimes a few of which are shown below - I can usually have a stab at what they are close to but haven't found anything in the books which exactly matches. It could be that they are simply immature forms of other species or simply poorly preserved, though the preservation on these looks quite good. More probably I just haven't recognised them. i80.photobucket.com/albums/j178/neuropteris/unknown4.jpgi80.photobucket.com/albums/j178/neuropteris/unknown7.jpgi80.photobucket.com/albums/j178/neuropteris/unknown13.jpgi80.photobucket.com/albums/j178/neuropteris/Unknown21a.jpgI've got mixed feeling about the loss of the site. Yes, its sad that its gone but the fact that it wouldn't be there forever gave me the impetus to go as often as I could which I probably wouldn't have done had I known it would be there forever and as it was worked there was always new material being exposed. As a result I managed to build up a good collection. At least now I can get on and do other things without wondering what I'm missing and there's every chance of new opencasts being opened nearby and exposing different horizons and a different range of plants and animals (fish nodules please!) Andy |
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Post by Joe Botting on Jan 18, 2007 16:14:16 GMT -5
Hi Andy, Many thanks for that -it tells me how little I know of Coal Measures ecology! It sounds as though the ecology is much more complex than I thought, with a susprisingly high diversity of 'species...' Next question, though - do you think the species are really distinct, or are they merely morphs and ecophenotypic variation (i.e. due to different light levels, etc.)? Look at some modern ivy, for example, and leaf shape is all over the place, on the same plant. But perhaps Ivy's more variable than ferns. I think I'll go have a look at the Proc. Geol. Ass. paper, at least. I really hope you get more local sites to work on. You sound like someone who would very soon get an itchy hammer when deprived of new specimens. And I'll keep my fingers crossed for fish!  Cheers, Joe |
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Post by neuropteris on Jan 19, 2007 7:50:35 GMT -5
Hello Joe
There have been studies which show different communities of plants inhabiting different environments of the coal swamp, Lycopods such as Lepidodendron and Sigillaria dominating the swampy mires and a more mixed community of Pteridosperms, ferns etc growing on the levee banks. Many plant fossils represent debris transported from their site of growth by floods etc so they are only indicative of the local community. The fact that they are fragmentary also makes identification of the whole organism problematic. Certainly I think leaf morphology can be variable based on what I've seen. If I'm sounding a bit vague its because to be honest I don't really know. I've often tried to identify finds down to species level using keys such as the Cleal and Thomas book but fail because many of the distinguishing features a so similar (eg veination patterns) or aren't preserved in the specimens I've found. It can be quite frustrating!
I must get the Proc Geol Ass paper myself - I only came across the reference when I was reading up to try to answer your question. Sounds very interesting. I've just got hold of a new guide to the Mazon Creek plant material "Mazon Creek Fossil Flora" by Jack Wittry in the US which gives an updated review of the material from there. Great colour photos aswell.
The hammer is indeed itchy, not to mention rusty. Must get out again soon if only for ammonites
Andy
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