Who are the orchids?

Prompted by a visit to Wisley earlier today, to find out what the orchids are. My prior knowledge stopped after thinking that there were a lot of them and that they were mainly tropical. And knowing that pyramid orchids are quite common in the parts of the south east that we know. There have been quite a lot of posts about them.

From reference 1, I learn that there are maybe 30,000 species of orchid - and that is not including all the many hybrids. Around 70% of these species are epiphytes, mainly living perched in trees in wet, tropical forests. Not parasites, but lazy.

From reference 2, I learn that orchids, a family, are monocotyledons. They are distinguished from other monocotyledons by certain peculiarities of their flowers, one of which is the inferior ovary.

The flowers all have three sepals (one up and two down) and three petals (two up and one down). The down petal is often highly specialised. Bilateral rather than radial symmetry. Male and female sex organs, starting with the ovary below the flower proper, are carried on something called the column.

From reference 3, I learn that the flowering plants, the angiosperms, are divided into two sub-classes, the dicotyledons and the monocotyledons. Roses and cabbages, for example, are families in the first of these, grasses, lilies and orchids are families in the second. but in the jargon of the cladists, monocotyledons are monophyletic - they have a proper common ancestor - and are better, as far as that goes, than the dicotyledons which are paraphyletic, with rather more mixed ancestry.

Reference 4 offers a more complicated version of this story, elaborating the higher level groupings - clades such as euangiosperms, eudicots and core eudicots - which, as reference 3 had already pointed out, is very much work in progress. The core eudicots, aka core tricolpates, include the roses and cabbages. Colpate is to do with the shape of pollen grains, the presence or otherwise of various kinds of furrow or groove.

The snap above, of striate-tricolpate (fossil) pollen, taken from reference 6 and turned up by Bing seems a good place to stop.

PS 1: in the olden days, the split between monocotyledons (primitive) and dicotyledons (advanced) appeared to be both simpler and more basic than appears to be the case now.

PS 2: Monday morning: Sunday was also the day that the Atlantic Storm Beryl caught my eye. I now know that there had been a relatively feeble Storm Alberto earlier in the month and that the alphabetical lists of names are established years in advance. With 21 names on the core lists, which miss out Q, U, X, Y and Z - unlike the Nato alphabet (which I still recite from time to time and occasionally use when talking with the hard of hearing) and which does all 26 letters. Read all about the splendid bureaucracy involved at references 7 and 8. While NATO is to be found at reference 8.

References

Reference 1: Orchid - Dan Torre - 2023.

Reference 2: Britain's Orchids - David Lang - 2004.

Reference 3: Guide to flowering plant families - Wendy B. Zomlefer - 1994. University of North Carolina Press, Chapel Hill.

Reference 4: The tree of life: a phylogenetic classification – Lecointre and Le Guyader – 2006.

Reference 5: https://en.wikipedia.org/wiki/Orchid.

Reference 6: The ultrastructure of angiosperm pollen from the Lower Cenomanian of the Morondova Basin, Madagascar - Michael S Zavada - 2003.

Reference 7: https://www.nhc.noaa.gov/aboutnames.shtml.

Reference 8: https://www.nhc.noaa.gov/aboutnames_history.shtml.

Reference 9: https://psmv4.blogspot.com/2020/08/breaking-rhythm.html.