Biodiversity

Video: Example of Biodiversity (PE)

Biodiversity  Biodiversity means a variety of living organisms (Bio = Life; Diversity = variety)

Importance of Biodiversity Case Study  If honey bees die out completely, only wealthy people would be able to afford things like beef and ice cream. Why?

Importance of Biodiversity Case Study  North America used to have more than 4000 different animals that pollinated plants.  Honeybees were introduced from Europe in the 1800’s and outcompeted other pollinators.  Today, honeybees are declining rapidly and are one of few animals that act as pollinators  Decrease in biodiversity = less resilient environment

Importance of Biodiversity Case Study  The link between honeybees and ice cream… Pollinates Is food for Produces

Importance of Biodiversity Case Study  What conclusions can we make based on the honeybee case study?  The loss of a single organism has far reaching consequences  Species are all interconnected via food webs and through other special relationships  Honey Bees are a keystone species  Biodiversity maintains ecosystems

Levels of Biodiversity 1. Genetic Diversity 2. Species Diversity 3. Ecosystem Diversity

1. Genetic Diversity  The sum of all the genes present in a particular species  Species: Members of a population that look similar and can breed with each other to produce viable offspring  Each organism within the same species has a different combination of genes (DNA) which is what makes every organism unique  This also allows for populations of species to adapt to changes  E.g. Resistance to disease

How Genetic Diversity Allows Adaptations  Imagine that a severe drought were to affect the Savannah and only tall trees could survive. What would happen if all giraffes were like giraffe “A” or giraffe “B”? * The giraffe population would decrease or become extinct ABC

2. Species Diversity  The variety of species in a given area  Having a high variety of species in an ecosystem allows the environment to survive droughts, plagues, disease, etc.

2. Species Diversity  E.g. How might this ecosystem manage if a disease impacted the entire rabbit population? * The Wild Cat and Jackal would become more dependent on other prey

3. Ecosystem Diversity  A diverse range of habitats, the organisms that live in those habitats, and the relationships that connect them.  Any change to a single part of an ecosystem will have some effect on the entire ecosystem but the greater the ecosystem diversity to better able it is to stay balanced

3. Ecosystem Diversity  Genetic and species diversity helps to maintain ecosystem diversity. (it takes both into account)

In Conclusion  Why worry about biodiversity?  It protects our food supply, maintains ideal conditions for human life, and ensures resilience through harsh conditions. Further Evidence: Sichuan, a small town in China, controlled pests by spraying pesticides over their crops. Unfortunately, these pesticides also killed the honeybees. As a result, humans had to pollinate the pear trees. This takes longer, costs more, and is much less effective. If we were to do this in Canada it would cost $20 billion in wages and only a fraction of the trees would be pollinated!

Homework  Read pages #1-5, 9-10 (p.37)