In message , Nick Maclaren
writes

In article ,
Broadback writes:
|
| Using Latin names is confusing enough for me, but why do they so often
| seem to change plant names?

Fundamentalist dogma.

Seriously. There was an agreement on how to slected a particular name
if several authors had used different ones for the same species, or if
what were two species turned out to be variants of one. Fine. All
well and good, but the (botanical) religious ferverts got the upper
hand over the (horticultural) pragmatists and turned a sound rule into
a Holy Doctrine.

There is a pragmatic rule for genera, which is very necessary to avoid
generic names changing every time someone discovers a mouldering paper
to the Botanical Society of Novosibirsk in 1800. But there is no such
rule for specific names, which is why we get abominations like Viburnum
farreri - which is STILL called V. fragrans in horticulture, quite
reasonably. This interacts with the ongoing war between the 'splitters'
and 'clumpers' religious sects, because they need to fiddle the names
every time they reshuffle the species.

There is a pragmatic rule for species as well, if you're talking about
conservation of widely used names over earlier published names. For
example Adansonia gregori (the Australian baobab) is conserved over
Adansonia gibbosa, and Luehea speciosa over Luehea alternifolia.

One other cause of name changes is embracing of the principle of
monophyly by taxonomists, combined with new data from DNA sequencing.
(The whole of Cactaceae is nested in one genus of Portulacaceae, but
this is 'fixed' by splitting that genus - not by the joking suggestion
to sink all several thousand species of cacti into that genus; and all
other genera of Cactaceae into the genus Perevskia - I haven't seen a
proposed solution for this. Data is not always unambiguous, so botanists
tend to be conservative about changing generic circumscriptions -
waiting until the data is clear.)

There's problems in the pipeline with Hibiscus, and even with generic
circumscriptions between Malva, Lavatera and Althaea.

All right, that's the jaundiced viewpoint, and you can can equally well
spin the same facts into a 'best effort' solution to an intractable
problem, handicapped by reactionary and carping ignoramuses :-)

The root cause is that, as Oscar Wilde said, the truth is rarely pure
and never simple. And dividing even the higher plants into species
is most definitely a truth of that form! So all schemes will be
unsatisfactory, and arbitrary rules are needed but absolute ones will
always get individual cases wrong. It IS an intractable problem.


Regards,
Nick Maclaren.

--
Stewart Robert Hinsley