Download invasive species

Mimicry
•
•
__________ mimicry
– Palatable insects resemble brightly
colored, distasteful species.
 non-poisonous Viceroy butterfly looks
like the _____________
___________ mimicry
– Unrelated protected species resemble one
another.
 predators learn more quickly
 Several distasteful butterflies look alike
1
Coevolution and Symbiosis
•
Coevolution involves long-term mutual
evolutionary character adjustments of two or
more species.
– predator-prey interactions
– symbiotic relationships
 long-term relationships.
 Give an example of each:
commensalism, mutualism, and
parasitism
2
Interactions Among Ecological Processes
Keystone species
– Species that have a
particularly strong effect on
community composition.
 top predators may keep
one species from
outcompeting others
 Beavers build dams and
change ecology.
3
Succession
•
Succession is the process of ecosystems
changing from a simple to a more complex
structure.
– primary succession - occurs in bare or
open areas
 eutrophication (adding nutrients) of
oligotrophic (poor in nutrients) lakes
 Lichens first, then mosses, then larger
plants.
– secondary succession - occurs only when
soil is already present
4
Invasive Species
•
•
What is meant by invasive species?
Give examples of invasive species in North
America, and describe the effect of each.
5
The Nitrogen Cycle
•
•
Nitrogen fixation: makes nitrogen that plants
can use to make proteins
– Mainly from symbiotic bacteria
– Ammonification-nitrogen fixation that
makes NH3 (ammonia) from N2 gas.
Denitrification- bacteria release N2 gas into
atmosphere
6
Trophic Levels
•
•
Autotrophs - capture light energy and
manufacture own chemical energy
– primary producers
Heterotrophs - must obtain organic
molecules that have been synthesized by
autotrophs
– consumers
7
Trophic Levels
–
–
–
Primary consumers - herbivores
Secondary consumers - organisms that
feed on herbivores
Detritivores - live on refuse of an
ecosystem
 Decomposers - break down complex
organic material into simpler compounds
8
Trophic Levels
9
Trophic Levels
•
•
Trophic level refers to the feeding level of an
organism.
– Organisms from each trophic level
constitute a food chain.
 Interconnected food chains constitute a
food web.
10 % rule- On average, 10% of the organic
matter (energy) transfers from one trophic
level to the next.
10
Primary Productivity
•
•
Primary productivity refers to the amount of
organic matter produced from solar energy
in a given area during a given period of time.
– Gross primary productivity is the total
organic matter produced.
– Net primary productivity is the amount of
organic matter produced that is available
to heterotrophs.
Secondary productivity - rate of production
by heterotrophs
11
Types of Parasites-Trivial
•
•
•
•
Ectoparasites live on the surface of their
host (outside) ex: tick..
Endoparasites live inside their host ex:
hookworm.
Mesoparasites live part of life cycle inside
and part outside. Ex: Apicomplex that
causes malaria.
Parasitoids- larvae eat their host and often
kill , so they are really more like predators.
12