1. Chapter 4: Ecosystems and Communities
4-1 The Role of Climate

2. Climate Climate: long-term, averages, over entire biome
Weather: short-term, local day to day
Greenhouse Effect
It’s a good thing!
CO2, H2O, CH4 all trap heat and hold it next to the surface
Keeps the temp suitable for life Solar Energy

3. The Effect of Latitude on Climate
Earth has 3 climate zones due to unequal heating because of the angle of the sun. Most intense heating is near the equator.
Polar
Temperate
Tropical

4. Heat Transport Ocean and wind currents help produce Earth’s climates
The ocean is a huge heat sink for the earth.
Currents and winds are affected by land masses and Earth’s rotation

5. 4-2 Niches and Community Interactions

6. The Niche Niche – Where and How something lives; its role
Habitat is the organism’s address
Niche is the organism’s occupation

7. Dendrobates tinctorius dyeing poison dart frog
Contributors
Matt Jolman (author), Michigan State University. James Harding (editor), Michigan State University.
References
Obst, F The completely illustrated atlas of reptiles and amphibians for the terrarium. Neptune City, NJ: T. F. H..
Walls, J Jewels of the rainforest. NJ: THF.
An analysis of niche
Poison Dart Frog – discovery
Camouflage

9. What defines a niche? Where it lives What it eats What eats it
How it reproduces
Humid, wet habitats; on or close to ground
(skin is not waxy enough to prevent dehydration)
South America
Tadpoles eat almost anything
Adults = insectivores; ants termites, spiders
Few predators – poisonous
Eggs laid on land, male fertilizes directly over top and then carry the nearly hatched tadpoles on his back to water.

10. What defines a niche…cont…
What nutrients it needs
Movement
Range of tolerance
How it interacts with others/abiota
Role it plays in energy flow and nutrient cycling
Needs natural diet to create poisons. Toxins not produced on captive diets (lack alkaloids)
Finger & toe tips have glandular adhesive pads that enable climbing
70-80F, 60% humid, 10hr light, Cl-free water
Stands out b/c it’s poisonous
Respires through skin, consumer (omnivore)

11. COMMUNITY INTERACTIONS Problem: 2 niches overlap
WHAT IS YOUR SOLUTION?
Migrate
Change feeding habits
Adapt behavior
Suffer a sharp population decline
Become extinct in that area
What type of species overcome this more easily?
Generalists
or Specialists?
generalist

12. Phrased another way: I want something that you want…
Will we compete?
Will I eat you?
Will we work together some how?
In nature, there are 3 basic types of interactions…
Competition
Predation
Symbiosis
Phrased another way…

13. Community Interactions
Competition
Organisms compete for resources
Ex: Food, Mates, Shelter
Competitive Exclusion Principle – no 2 organisms occupy same niche at same time.
Predation
One organism (predator) captures and feeds on another (prey).

14. Community Interactions
Symbiosis
Mutualism – both benefit
Ex: Flowers & insects
Egrets & Alligators
Clown Fish & Sea Anemone
Commensalism – one benefits, the other is not helped or harmed
Ex: Barnacle & Whale
Parasitism – one benefits, other is harmed
Ex: tapeworms, fleas, ticks, lice

15. Community Interactions
Symbiosis
Mutualism – both benefit
Ex: Tapeworm
Commensalism – one benefits, the other is not helped or harmed
Ex:
Parasitism – one benefits, other is harmed
Ex: tapeworms, fleas, ticks, lice
Species Interactions

16. Examples of Symbiosis

17. Invasive vs. Native Species Indicator Species Keystone Species
Specialty Niches
Invasive vs. Native Species
Indicator Species
Keystone Species

18. Invasive Species Purple loosestrife & Kudzu
Introduced by accident (zebra mussels like quaga mussel in life after people and green crab); introduced on purpose (ornamental loosestrife & kudzu to control erosion in the southeast but took over)
Purple loosestrife
& Kudzu
Carcinus maenus, the European Green Crab, was
introduced to North America in the 1800's. This predator
now ranges from Nova Scotia to Delaware.

19. 3 examples: Macquarie Island / Pythons/Asian Carp
(to 6:30)

20. Native Species

21. Indicator Species
Indicates the health of the ecosystem

22. Keystone Species Kelp forest Sea Otter Dung Beetle
A keystone species is a species that plays a critical role in maintaining the structure of an ecological community and whose impact on the community is greater than would be expected based on its relative abundance or total biomass.
Kelp forest
Sea Otter
Dung Beetle

23. Foundation Species
species that create habitats for themselves and a wide range of other species

24. 4.3 ECOLOGICAL SUCCESSION
Biosphere
Ecosystems
Communities
Populations
Organisms
4.3 ECOLOGICAL SUCCESSION

25. What is succession?
TIME

26. Is Disturbance a Good Thing?
Life is always changing
and then responding to that change.
Plant (& therefore animal) species are constantly being replaced with more complex species
This is called ecological succession

27. Arrange the pics in the correct order…

28. Ecological Succession
Primary OR Secondary Succession?
Depends on starting conditions:
Is there any soil present?
Does not matter if life had been there previously or not

29. PRIMARY SUCCESSION Lifeless beginnings Starts WITHOUT SOIL. Examples:
Bare rock exposed by glaciers or severe erosion
Newly cooled lava
Abandoned highway or parking lot
Newly created shallow reservoir

30. PRIMARY SUCCESSION Life begins with PIONEER SPECIES Hardy, small
Population grows quickly
Grow close to the ground
Ex: bacteria, moss, lichens

33. SECONDARY SUCCESSION Starts WITH SOIL.
start from roots or seeds remaining or seeds carried in by wind or animals
Examples:
Abandoned farms
Heavily polluted streams
Ponds from dams or flooding

34. Succession of Plants
Pioneer species make an area suitable for more plants
A process called “facilitation”
Early successional species
Can withstand little nutrient availability
A little taller than pioneers: small herbs, grass

35. Plant succession continued
Mid-successional species
Need more fertile soil w/ moisture
Must wait for some decomposition
Tall grass & low shrubs, eventually sun-loving trees
Late-successional species
Need deep, fertile, moist soil
Slow growth rate
shade tolerant trees

36. Climax Community Succession is unpredictable
While it generally proceeds from small to tall, each disturbance is unique and each pioneer is unique…leading to unique community developments
The most mature community is called the climax community

37. Primary on top, secondary on bottom: difference is soil starting point

38. / 38

39. Disturbances can lead to opportunity for others
Hurricanes…
In S. Fla. the Everglades depend upon the periodic hurricanes for the continued existence of the mangrove.
Why?
Primary or secondary?
Importance of Mangroves

40. PUT IN ORDER OF SUCCESSION
POND SUCCESSION
Review
PUT IN ORDER OF SUCCESSION 40

43. M&M’s Weather vs. Climate
Red = Warm and Sunny
Yellow = Warm and cloudy
Green = Cool with light rain
Blue = Cold with steady rain
Orange = Hot, sunny
Brown = Hot very humid and sunny