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Macromolecules (e.g. DNA, proteins)

Cells

Tissues and organs

Organisms

Molecular subunits

Populations

Communities

Ecosystems

Species

Phyla

Biology is hierarchical

Atoms

Genera

Kingdoms

B i o d i v e r s

i t y

Why study biodiversity, ecology, andconservation biology?

What is biodiversity?

How do biologists organize biodiversity?

Why is biodiversity important?

What is the biodiversity crisis? How can we protect biodiversity?

Earths biodiversity Earths biodiversityBiodiversity the diversity of life on Earth

variety at all levels of biological organization

Components of biodiversity:

Genetic diversity genetic variation within populations

or species Species diversity numbers of species within an area

Diversity among higher taxa variation between genera,families, orders, etc.

Ecosystem diversity variation among ecosystems,communities, landscapes

Are different groups of organisms equally diverse?

Are different parts of the world equally diverse

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How many species are there?

about 1.5 million species have been named

estimated to be between 5 and 30 million species on Earth

Actual biodiversity an inordinate fondnessfor beetles

How is biodiversity organized? Regions and ecosystems vary in biodiversity

Biodiversity hotspots regions with very high biodiversity mainly in the tropics , also islands , some other areas

Diverse ecosystems tropical rainforests, coral reefs, islands

Endemic species found only one place in the world, often on islands

Variation among regions and ecosystems inspecies composition and species diversity

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Economic value resources, including food medicines and other helpful chemicals genes for better crops opportunity cost

Utilitarian value prevent erosion purify water recycle CO 2 regulate climate recycle nutrients through decomposition

collectively, ecosystem services

Psychological value direct or indirect enjoyment of nature

Intrinsic value independent of humans

Why is biodiversity important?

Humans are causing extinctions at a tremendous rate .

~100 times faster than expected without human activity

parallels or exceeds previous mass extinction events

What is the biodiversity crisis?

current rate of extinction is at least 100x background

What if extinction > speciation?

What is the biodiversity crisis?

Why is the loss of biodiversity a crisis?

economic value of biodiversity lost or threatened

ecological services lost or threatened

ecosystems more vulnerable to further degradation

Humans are causing extinctions at a tremendous rate .

~100 times faster than expected without human activity

parallels or exceeds previous mass extinction events

habitat destruction and fragmentation

What are the biggest threats to biodiversity?

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habitat destruction and fragmentation

habitat modification

What are the biggest threats to biodiversity?

habitat destruction and fragmentation

habitat modification

introduced species

What are the biggest threats to biodiversity?

habitat destruction and fragmentation

habitat modification

introduced species

overexploitation

What are the biggest threats to biodiversity?

Human population growth exacerbates all of these threats.

habitat destruction and fragmentation

habitat modification

introduced species

overexploitation

What are the biggest threats to biodiversity?

What is the biggest terrestrial threat? marine?

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the science of protecting and restoring biodiversity and ecological health

ecology

evolutionary biologygeneticsphysiology

basic principles goals

maintain biological diversity

and ecosystem health

What is conservation biology?

an applied science

applied to

apply ecological and evolutionary principles :

to understand biodiversity and ecosystem functioning

to understand threats to biodiversity and ecosystem health

ultimately, to protect and restore biodiversity and ecosystem health

What do conservation biologists do?

What makes a healthy ecosystem?

How can we protect and restore biodiversity and ecosystem health?

What makes a healthy ecosystem?

intact structure and function

Functional groups,e.g., pollinators:

Trophic levels:

What makes a healthy ecosystem?

intact structure and function

+

Keystone species:

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What makes a healthy ecosystem?

intact structure and function

Nutrient cycling:

Ecosystem services,e.g., water purification:

What makes a healthy ecosystem?

intact structure and function

resiliency of ecosystems to stress

Diversity:

What makes a healthy ecosystem?

intact structure and function

resiliency of ecosystems to stress

Complexity and functional redundancy:

What is a species?

What determines whether species evolve or die?

Where does genetic variation come from?

What determines whether populations grow or crash?

How can competing species coexist?

Why do ecosystems differ in biodiversity?

How do communities and ecosystems work?

What causes extinction?

How do ecology and evolution inform conservationbiology?