On 8 August, two stories were published. One of them provided hope; the other a sense of great loss.

The first told how six new species had been discovered in a remote forest in the Democratic Republic of Congo. Dr Andrew Plumptre from the Wildlife Conservation Society commented:

If we can find six new species in such a short period it makes you wonder what else is out there.

In the light of the second story, it also makes you wonder what else might have disappeared before we even knew it existed.

There had been a plan to save the
Yangtze River dolphin from extinction. However, it seems it may have been too little, too late. The Yangtze dolphin had been around for over 20million years; but couldn't cope with an heavily industrialised world and the demands the increasing human population were making on its environment. It's thought the main factor behind the dolphin's extinction was getting caught in nets and becoming part of the by-catch of the local fisheries. Dr Turvey from the Zoological Society of London stated:

This extinction represents the disappearance of a complete branch of the evolutionary tree of life. The Yangtze river dolphin was a remarkable mammal.

It was the only remaining member of the Lipotidae, an ancient mammal family that separated from other marine mammals (including whales, dolphins and porpoises)about 40-20million years ago.

If this report is confirmed to be true, it would be the first extinction of a large vertebrate for over 50 years.

• It's an impossible question to answer – but it's an important one to consider. How many creatures do you think could be becoming extinct without us ever knowing about them?

• The saying goes: you can't miss what you've never had. If we never knew about these creatures in the first place (or only knew about them for a small while), do you consider their loss really a great tragedy?

• Lord Alfred Tennyson said: 'nature is red in tooth and claw.' Charles Darwin said it's 'survival of the fittest.'
  If the dolphin was not suited to surive in our modern world, could its loss be attributed to natural selection?

• What can be done to stop this? Countries need to develop their economies and provide for their people, but how high is too high a price to pay?