Diversity of ecosystems Flashcards
What is an ecosystem?
An area of habitat with a relatively self-contained food chain/web.
What are the functions and services in an ecosystem?
Function - Processes that occur within ecosystems (e.g. primary production)
Services - When function benefits humans (e.g. Food production)
How are habitat types usually based on human perception?
- Dominant features
- Physical substrate
- Climate
- Large mammals
What are the problems with conserving habitat types?
Habitats are biased by human body size and senses.
Microhabitats may be more important to particular species (e.g. bark, rotting wood, etc)
Give an example of a species that requires multiple different habitats to survive.
Newts and dragonflies have different morphological stages in life.
How was diversity during the time of Pangaea the supercontinent? And when did this change?
Global biodiversity was relatively low, as everything was connected. It was only after 200 mya when the continents separated that adaptive radiation took place.
What are the characteristics of island endemic species?
Small populations
Vulnerable to invasion by continent species and catastrophic events (e.g., Tsunami).
What other environments are home to endemic species?
Isolates peaks and ridges - These are completely different environmental conditions.
What are the anthropogenic effects on ecosystems?
Humans modify and simplify habitats introducing species thus lowering alpha biodiversity.
What is a ‘Rifle’ shot extinction?
When a single species is driven to extinction but the ecosystem remains intact.
What is a Blitzrieg extinction?
When an entire ecosystem is disrupted it results in the extinction of many species.
Does the loss of species really matter?
Extinctions of endemic species reduce functional diversity of island ecosystems which leads to a potential loss of ecosystem services.
Extinctions also increase the similarity between island ecosystems.
How do ecosystems shift?
Anthropogenic changes exacerbates climate change and/ or biodiversity.
Give an example of a species that dominates when ecosystems are disrupted.
Jellyfish -
When they increase in number they predate on the juvenile offspring of their predators therefore this prevents the predator’s recovery.
What are keystone species?
These are species that when removed from an ecosystem cause an ecosystem shift. (e.g., Sea otters which predate purple sea urchins which without the presence of sea otters would destroy Kelp forests.
