1. What it is & why it matters.
Biodiversity
What it is & why it matters.

2. Biodiversity
refers to the number and kinds of organisms on the planet; a measure of life’s diversity.
genetic diversity (intraspecific) – within a species
Taxonomic (interspecific) diversity = between species
ecosystem diversity.
Biodiversity is the source of all human food, domesticated breeds of animals and plants, as well as bio-based medicines.

3. Life on our planet:

4. Life on our planet:

5. A matter of perspective:
Anthropocentrism = human-centred views of life, nature, the universe…
We relate most to those living things that have most in common with us
Familiarity: We identify things we have experienced directly… microscopic species?
Numbers: 2 Million known species, but there are estimates from 10 to 100 million out there.
Conservative estimate: 20 million species of life

6. Intraspecific Biodiversity:
All members of a species are different, due to differences in their genes.
Sources of genetic difference:
Different Parental DNA
Population Gene frequencies
Gene changes – Mutations.
Non-random mating
Human interference

7. Intraspecific Biodiversity
Burchell’s Zebra shows variation in striping across its natural range, yet they can all interbreed readily.

8. Intraspecific Biodiversity
Humans have modified many animals to suit our needs or whims, yet they remain one species, capable of interbreeding with very different looking breeds of their species.

9. Interspecific Biodiversity:
Species differ from one another because of their evolutionary ancestry
A species’ family tree over time is its phylogeny.
Different lineages have different genes
Results in many species of similar organisms.
Members of different species cannot mate with one another successfully.

10. Interspecific Biodiversity:
The primates from the previous slide are evolved from divergent lineages all descended from some very distant common ancestor.

11. Interspecific Biodiversity:
Over time, the ancestral forms that gave rise to the modern horse became extinct, but all were varied in their traits & adapted to changing environments.

12. Ecological Biodiversity:
Some general trends on our planet:
Closer to the equator, more species diversity
Why? Stable climate, and more direct solar energy = more biomass to support the food chain.
Harsh environments lead to extreme adaptations in the organisms living there
Geographic Area:
# of breeding bird species:
Greenland 56
Labrador 81
Newfoundland
118
Eastern USA
195
Guatemala
469
Colombia
1525

13. Canada’s Biodiversity:
Group
Known Species
Est. Still Unrecorded
Fungi
11800
3800
Plants
4934
135
Molluscs
1500
Arachnids
3275
7730
Crustaceans
3139
1400
Insects
18350
Fish
1100
513
Reptiles 42
Birds
426
Mammals
194

14. Canada’s Biodiversity:

15. Global Biodiversity:
Distribution of Bird Species

16. Global Biodiversity:
Distribution of Plant Species

17. Global Biodiversity:
Distribution of Mammal Species

18. Global Biodiversity:
Biodiversity Hotspots

19. Threats to Biodiversity
Mainly habitat loss or damage, due to human population expansion.
Estimated 2700 species can become extinct in a year…. That’s 3 per hour!
Our impact is not new: Humans colonizing North America years ago led to the extinction of species such as the horse, mammoth, sabre-tooth cat, and camel.
Similar impact when humans settled Polynesia years ago, New Zealand 1000 AD., Madagascar 500 AD…

20. Why Biodiversity Matters
Ecosystems need all of their organisms. Losing one or two species might create a domino effect of collapse.
Our food supply depends on diversity.
“Useful products can not be harvested from extinct species. If dwindling wildlands are mined for genetic material rather than destroyed for a few more tons of lumber or acrage of farmland, their economic yield will be vastly greater over time. Salvaged species can help to revitalize timbering, agriculture, medicine, and other industries.” – E. Wilson, Diversity of Life