View previous topic | View next topic

Denomination: plants

Page 1 of 1

MatC
62915.  Thu Mar 30, 2006 3:22 pm Reply with quote

Preamble:
Fingers on buzzers for a multiple choice question - one buzz for A, two buzzes for B, and the interval theme from Ben Elton’s Rod Stewart musical for C ...


Question:
How many species of plant are there on earth?
a) more than you think;
b) less than you think;
c) about as many as you think?


Forfeits:
Loads.

Answer:
Less. Probably.


Notes:
Nobody knows how many species of plant there are in the world, and one of the reasons for this is the problem of synonymy.

Two recent studies have come up with the figure of around 420,000 plants (or, strictly speaking, what are called “seed plants”). Kew Gardens keeps a list of every plant that’s ever been named and described. That list has just over a million names on it. But everyone accepts that a lot of those names are synonyms - the same plant has been “discovered,” and therefore named, more than once.

Two Oxford University academics recently looked into the puzzle, by studying about a dozen genera in detail, and going back to the original plants - usually pressed specimens in a herbarium.

The results of this study were astonishing - the average rate of synonymy was 78%. So every plant, on average, had about four names. If this figure is applied to the whole of the Kew collection, it would mean that the number of known plant species on Earth would tumble to only 223,300.

However, extrapolation may be risky, since the Oxford survey only involved 0.2% of the total collection. Another study suggests a synonymy rate of 66% - either way, it seems likely that there are far fewer species on the planet than previously thought.

Meanwhile, though, 2,000 new species are discovered every year ...



Links to:
DNA?

Picture ideas:



Sources:
Source: Organic Gardening, January 2006.

 

Page 1 of 1

All times are GMT - 5 Hours


Display posts from previous:   

Search Search Forums

Powered by phpBB © 2001, 2002 phpBB Group