Lecture 1: The Biodiversity Crisis: Science and Understanding 2

Question 1

Domestic cats

Answer 1

Domestic cat (Felis catus) c. 63 million pet cats and 30 million feral cats in the USA
• Feral cats alone kill c. 3 million birds a year in each state, translating to 240 million birds/year in total

Total damage to U.S. bird population is approximately $17billion/year

• Does not include the number of birds killed by pet or urban cats, thought to be similar to the number killed by feral cats; nor does the cost include the many small mammals, amphibians, and reptiles that are killed by feral and pet cats

Question 2

International treaty

Answer 2

An international treaty adopted at the Rio de Janeiro Earth Summit in 1992, and put into force in Dec 1993

• Requires a commitment from each nation to sustainably manage its biodiversity resources – a key law for sustainable development
• 189 countries have so far ratified the agreement – 1 country has signed but not ratified (United States)
• Sustainable management of urban green networks for biodiversity is an important challenge – monitoring of biodiversity is a requirement

Question 3

Direct use- food

Answer 3

Food
• Entire food industry and human survival
• Of c.300,000 flowering plants, c.12,500 are edible, though 75% of food comes from 12 types of plant (though more than 12 species)

Question 4

Direct use- medicine

Answer 4

60% of the global population relies primarily on plant medicine
• Plant-based chemicals have been used historically and synthesised to provide medicine

Question 5

Direct use- industry

Answer 5

Industry

• Directly obtained from or inspired by biodiversity, e.g. building materials, fibres, dyes, oils, chemicals…

Question 6

Direct use- recreation

Answer 6

Huge industry relying on species – key driver for conservation but also black market in endangered species

Question 7

Indirect use: existence and intrinsic values

Answer 7

Industrialisation has accelerated the loss, but it is not an entirely modern process, and it is important to recognise that perceptions and attitudes to biodiversity vary culturally

Question 8

Mora et al

Answer 8

compared predicted and recorded taxa at higher taxonomic levels and used this to predict species numbers. They predicted ~8.7 million (±1.3 million SE) eukaryotic species globally, of which ~2.2 million (±0.18 million SE) are marine

Question 9

How many species?

Answer 9

In spite of 250 years of taxonomic classification and over 1.2 million species already catalogued in a central database, our results suggest that some 86% of existing species on Earth and 91% of species in the ocean still await description”
• Taxonomic skills essential for improving this situation – now rarely taught