1. 2a- Ecology & Living Relationships

2. Principles of Ecology
Ecology – study of relationships between living and nonliving parts of the world
Ernst Haeckel (1866) – first to use the word to name the study of how organisms fit into their environment
Eco- earth

3. Interdependence All organisms interact with…
The other organisms around them
The nonliving parts of their environment
Survival depends on these interactions.
The dependence of every organism on its connections with other living and nonliving parts of its environment
Major theme in ecology

4. Interdependence White-tailed deer Acorns Humans Deer mouse Deer tick
Oak tree produces huge crop of acorns every few years. Lots of acorns supports larger populations of deer and mice, which feed on acorns. Ticks feed on the blood of animals, so tick population also increases. More ticks= more chances that ticks will bite any humans in the forest. Can transmit the bacteria that causes lyme disease
Deer mouse
Deer tick

5. Parts of the Environment
Abiotic factors – non-living parts of an organism’s environment
Air currents, temperature, moisture, light, soil
Biotic factors – all the living things that inhabit the environment

6. Ecological Levels of Organization
Organism
Population
Community
Biome- large region characterized by specific type of climate & certain types of plants/animals
Biosphere- inhabitable portion of the planet…the thin volume of Earth and its atmosphere that supports life
Ecosystem
Biome
Biosphere

7. Niche vs. Habitat vs. Ecosystem
Ecosystem – all the organisms in a given area and the abiotic factors that affect them
Habitat – the place an organism lives out its life
Niche – role and position a species has in its environment
Includes all biotic and abiotic interactions as an organism meets its needs for survival
If two species are competing for the same niche, one will most likely drive the other out and take control of the niche.
Niche- the specific way of life of a species within its environment – includes range of conditions that the species can tolerate, resources it uses, methods it uses to obtain resources, number offspring it has, time of reproduction
Plants and animals are able to share the same habitats because they each have different niches

8. Niche vs. Habitat vs. Ecosystem
An egret lives around Jones Pond which is part of the Smith River Estuary. The egret and its mate eat fish, frogs, salamanders, snakes, crayfish, mice, aquatic insects, crickets, grasshoppers, and a variety of other insects in Jones Pond and build a nest in a tree along side the pond.
What is the egret’s habitat?
What is the egret’s niche?
What is the egret’s ecosystem?
-Jones Pond
-tree, consumer, predator
-Estuary

9. Organism Interactions: Predation
The number of predators affects the prey population
More predators, more risk to prey
The number of prey affects the predator population
More prey, more food for predators

10. Organism Interactions: Competition
Competition – Organisms within a population must compete for resources
When populations grow, resources are in higher demand
If demand is greater than supply……population must decrease
Fight and kill each other
Reproduce less

11. Relationships
All living things form relationships with other living things
Symbiotic Relationship – a relationship between organisms of two different species that live together in direct contact
Symbiosis= longterm relationship
3 examples of symbiosis- commensalism, mutualism parasitism

12. Commensalism One organism benefits – The other is not affected
Examples:
Spanish moss on a tree
Barnacles on a whale
Burdock seeds on a passing animal
Spanish moss= epiphyte (plant that lives on another plant); makes it’s own food, doesn’t harm host tree

13. Mutualism Both organisms benefit
Acacia tree and ants – tree provides food for the ants and the ants protect the tree from animals that would eat the leaves
Lichens: algae and fungus living together Algae provides food (photosynthesis) and the fungus provides protection and attaches the lichen to the rock or wood where it lives.
- Bacteria living in human intestines: break down nutrients and have a safe environment

14. Parasitism One organism benefits, the other is harmed
Some live within the host
Tapeworms
Heartworms
Bacteria
Some feed on the external surface of the host
Ticks
Fleas
Mistletoe
Most do not kill their host (at least not quickly)

15. What is this?
Commensalism, Mutualism, or Parasitism?

16. Tube Worms and Hydrothermal Vents

17. Hydrothermal Vent Communities
Symbiotic Relationship: Bacteria live in Tube worms.
Worm has no digestive tract, so it relies on bacteria for nutrition.
Bacteria oxidize hydrogen sulfide that the tube worms supplies to them.
Both need each other to survive so what type of relationship?
Mutualism

18. Hydrothermal Vents are Pretty Rad.

19. Hydrothermal Vents