Last updated at 12:26 BST, Friday, 26 August 2011

Earth may house 8.7 million species

Summary

26 August 2011

A team of scientists has adopted a new approach to estimating the total number of living species on Earth, and has come up with 8.7 million. Their findings appear in the online journal, Public Library of Science Biology.

Reporter:
Paddy Clark

new species

Many species have yet to be identified and recorded

Listen

Click to hear the report:

Report

It's generally accepted that very many species have yet to be discovered, but until now nobody has devised a reliable way to find out just how many. Suggestions for total numbers have ranged from 3 million to a hundred million, but most of these have been no more than intelligent guesses.

Scientists from the Census of Marine Life devised a counting method by identifying numerical patterns linking data on known species. They reckon that there should be about 8.7 million types of living organisms, three-quarters of them animals and the rest plants.

However, since the introduction of the current classification system by Carl Linnaeus in 1758, only a million and a quarter have been catalogued.

The scientists warn that human activity is hastening extinctions, and they note a touch wistfully, that many of the hitherto unknown species may vanish before we even know of their existence.

Paddy Clark, BBC News

Listen

Click to hear the vocabulary:

Vocabulary

devised

came up with a plan

reliable

accurate

intelligent guesses

estimates based on a rational process of thought

reckon

calculate

classification system

grouping of organisms following pre-established patterns

catalogued

identified and recorded

hastening extinctions

speeding up the disappearance of some species

wistfully

sadly

hitherto

up to now

vanish

disappear

  1. Home
  2. Grammar, Vocabulary & Pronunciation
  3. Words in the News
  4. Earth may house 8.7 million species