This is a really interesting post on the Awkward Botany blog about alien species and the possibility of plant extinction.
In our current ‘Extinction or Survival?’ exhibition we have illustrated this potential threat to species using the stories of the red squirrel and the white-clawed crayfish in the UK, but of course competition with invasive species is a potential risk for plants too.
One of the concerns about introduced species becoming invasive is that they threaten to reduce the biodiversity of the ecosystems they have invaded. They do this by spreading rampantly, using up resources and space, altering ecosystem functions, and ultimately pushing other species out. In the case of certain invasive animals, species may be eliminated via predation; but plants don’t eat each other (generally), so if one plant species is to snuff out another plant species it must use other means. Presently, we have no evidence that a native plant species has been rendered extinct solely as a result of an invasive plant species. That does not mean, however, that invasive plants are not doing harm.
In a paper published in AoB Plants in August 2016, Paul O. Downey and David M. Richardson argue that, when it comes to plants, focusing our attention on extinctions masks the real impact that invasive…
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Yesterday saw a group of first-year undergraduates braving the baking Mediterranean sun for the first day trip of the Comparative and Adaptive Biology field course. The Bocquer Valley near the town of Pollenca is a great place to look for Mallorcan endemic ‘hedgehog’ plants Teucrium subspinosum and Astragalus balearicus. While the students investigated the distribution of these small spiny shrubs, the staff took the opportunity to do a little more plant hunting.
One beautiful plant we regularly see in flower is the Balearic cyclamen (Cyclamen balearicum). It has very marbled leaves and delicate white flowers and hides in the shade of the larger shrubs. We also find the leaves of the Mallorcan peony (Paeonia cambessedessii). We visit far too late to see it in flower, but we’ve never found fruit either, suggesting that these plants didn’t flower in February or March. Perhaps these are young plants, or perhaps this is an indication of the difficult environment in the valley. This peony is named for the French botanist Jacques Cambessedes (1799-1863) who studied the plants of the Balearic Islands in 1825 and published the account of his travels and his work on the flora in 1826 and 1827.
One plant we’ve not spotted on our previous visits is the Dead-horse arum (Helicodiceros muscivorus). Given that it was behind a tree, under a shrub and in the bottom of a drainage channel, it’s not too surprising that we’ve not found it before. This plant has striking arrow-shaped leaves (sagittate leaves) and a flower spike (spadix) enclosed in a sheath known as a spathe. This specimen had not yet opened, and the geometrically patterned spathe was still closed shut. I’m not sure that I was too disappointed as the plant attracts pollinating flies with heat and rotting carcass smells.
We come across plenty of specimens placed in newspapers – this one is from 1912! – Not all of them, like this one, are secured with tape. But, when they do have tape, we have to cut through the tape with either a knife (pictured) or a scalpel.
Once the specimen has been cut free; we then transfer the specimen to a new sheet.
Along with the specimen, we transfer all identifiable information to the new sheet.
The finished product, the specimen on its new sheet, secured with tape, and with the same information from its previous (newspaper) sheet.