Biodiversity

Biodiversity refers to the variety of

organisms in a given area

Biodiversity

Species RichnessWhen measuring biodiversity, the

number of different species and the number of individuals in each species is

important, a concept called species richness

Genetic DiversityWithin species, genetic diversity is also

important and signals a healthier population over time

Breeding Problems due to low numbers and inbreeding

99% identical DNA

Measuring Earth’s DiversityUsing species diversity as a measurement,

there are an estimated 10 – 30 million species on Earth with the largest proportion being

insects

Ecosystem DiversityTropical rainforests are the

most diverse of all the biomes, containing one-

fifth of all species on Earth.

Importance of BiodiversityDiversity breeds diversity. Different types of vegetation provide different habitats, different

sources of food, and different types of medicine

Anthelmintic

Anti-oxidant

Anthelmintic Immunity

Importance of Biodiversity The unknown factor.Everything is connected and through history

humans have made themistake of removing an organism only to find it led the loss of several other organisms and

sometimes the destruction of entire ecosystems.

Reducing BiodiversityThe number one threat to biodiversity is habitat

destruction

http://www.huffingtonpost.com/2013/04/30/koala-photo-loggers-australia_n_3179029.html

Reducing BiodiversitySince the agricultural revolution, humans have been changing diverse ecosystems

into monocultures

Reducing Biodiversity Another includes introducing non-native invasive species that outcompete native species or act as predators of native species that have no natural

defenses.

Reducing BiodiversityThe brown tree snake was introduced to Guam about

50 years ago by accident. Since there had never been snakes on Guam, the native birds had no

defenses against the brown tree snake. Today, only 2 of the original 12 native bird species still exist on

Guam.

Reducing BiodiversityOver hunting or over fishing have also taken

their toll on biodiversity

Reducing Biodiversity Pollution is another threat to biodiversity

as different habitats are degraded or animals are killed

EutrophicationEutrophication occurs when too much nutrients, such as nitrogen, from animal wastes become fertilizers for the algae which reproduce rapidly creating an algal bloom.

EutrophicationOnce the nutrients are consumed, the algae begins to die off and are decomposed. During decomposition, oxygen is removed from the water by the decomposers as a result of cellular respiration.Low levels of dissolved oxygen lead to fish kills

Reducing BiodiversityWide spread use of pesticides or “weed

killers” have also led to a loss in biodiversity, especially when rain washes it into the

waterways

DDT

Biomagnification is the process by which toxins increase in

strength and concentration as they travel up the

food chain

Effects of Pesticides Bioaccumulation is the process by which toxins are

stored and increase in concentration within the body of an organism

MetalsBesides pesticides, heavy metals such as mercury

and lead can also bioaccumulate in organisms and result in biomagnification.

Mercury usually enters the water as a result of coal

burning plants and bioaccumulate in fish. In

humans, mercury poisoning results in birth

defects and brain damage.

Acid RainAcid rain is created when sulfur oxides and nitrogen oxides from the burning of fossil fuels, mainly at coal

burning plants, combine with rain to make it more acidic

Coal Plants

Acid RainAcid rain contaminates the water of rivers

and lakes, causing reproductive problems in aquatic animals and sometimes death.

Acid RainAcid rain washes minerals such as calcium and

magnesium from the soil that plants need to grow