1. Ecology

2. What is Ecology?
The scientific study of interactions among and between organisms and their environment, or surroundings
“study of the house”
Relatively new field of study ’s

3. Levels of Organization
Organism—a living thing

4. Levels of Organization
Species
Group of similar organisms
Able to breed and produce fertile offspring
Population
Group of individuals of the same species
Live in the same area

5. Levels of Organization
Community—several populations living in the same area

6. Levels of Organization
Ecosystem—collection of all the organisms that live in a particular area AND their nonliving environment
Organisms Environment
Plants Weather
Animals (including humans) Oceans
Fungi Soil
Microorganisms Volcanoes

7. Levels of Organization
Biome—groups of ecosystems with the same climate and similar communities

8. The Biosphere All portions of the planet where life exists
Land
Water
Air/Atmosphere
The biosphere is dynamic (ever-changing.)
It is the highest level of organization that ecologists study.

9. Ecological Methods
Three basic approaches are used by scientists in ecological research.
Observing
Often the 1st step
Simple or complex
Experimenting
In labs or in natural ecosystems
Modeling
Phenomena that occur over long periods or on large scales

10. Energy Flow Organisms need energy to power life’s processes.
Sunlight is the main energy source for life on Earth.
Some types of organisms rely on the energy stored in inorganic chemical compounds.

11. Producers and Consumers
Autotrophs (able to make their own food)
Plants, some algae and certain bacteria
Photosynthesis or chemosynthesis
Consumers
Heterotrophs (must eat other organisms for food)
Herbivores, carnivores, omnivores,
detritivores, decomposers

12. Feeding Relationships
Energy flows through the ecosystem in ONE direction.
Sun/Inorganic Compounds Producers Consumers
Food Chain—Series of steps in which organisms transfer energy by eating and being eaten.
The arrow  indicates which way energy flows (i.e. from the plant to the animal.)

13. Food Chains A food chain shows what is eaten.
The fly is eaten by the thrush.

14. Food Chains A food chain shows what is eaten.
The lettuce is eaten by the rabbit.

15. A Basic Food Chain
Plants absorb light from the sun, which is turned into energy to grow. We call these producers.
The vegetarian animals eat the plants, they are called primary consumers.
Secondary consumers prey on primary consumers.

16. Food Chain Simplest feeding relationship

17. Food Web

18. **Only about 10% of energy is transferred from one trophic level to the next.

19. Tertiary Consumers
Secondary Consumers
Primary Consumers
Producers

20. Cycles of Matter
Unlike the one-way flow of energy, matter is recycled within and between ecosystems.
Biogeochemical Cycles
The Water Cycle
The Carbon Cycle
The Nitrogen Cycle
The Phosphorus Cycle

21. Water Cycle

22. Batteries
Batteries have harsh chemicals and should be dispose of properly
Rechargable can be reused and reduce chemicals introduced into ground and water source

23. Antibiotics Don’t flush unused medicine
Increase numbers of medicine found in water.
Possible increasing resistance in bacteria

24. Carbon Cycle

25. Greenhouse Effect
Natural situation in which heat is retained by a layer of the greenhouse
Carbon dioxide, water vapor, methane and other gases trap heat energy

26. Fossil Fuel verses others
Fossil Fuel is pulling carbon out of the ground and adding it back to the cycle (increasing Green House Effect)
Higher prices currently and source of fossil fuel is decreasing
Ethanol is using carbon above the ground and not reintroducing carbon not currently in the upper cycle.

27. Other uses of corn
One source of ethanol is corn, but it is used to feed cows and food we eat.
Instead of growing wheat, a farmer may opt to grow corn due to the price paid
This raises the price of bread, and the price goes up on milk too since feed for the cow goes up.

28. Energy Solutions?
Wind--clean, drawback is birds tend to die in the turbines
Solar is still expensive to build and limited to daylight
Hydro-water is limited to water sources, and changes ecosystems
Nuclear has waste that must be dealt with in a special manner and the core may overheat

30. Phosphorus Cycle

31. Nutrient Limitation
Primary Productivity—rate at which organic matter is created by producers
Limited by the availability of nutrients
If there is too much of a
certain nutrient available,
problems such as algal
bloom can occur.

32. Ecosystems Composed of Biotic Abiotic
Biotic factors (living organisms)
Abiotic factors with which they interact
Biotic Abiotic
Plants Weather
Animals (including humans) Oceans
Fungi Soil
Microorganisms Volcanoes

33. Habitat
The place
where a
species lives

34. Niche The role an organism plays in its environment.
Some niches are small (ie. Pandas only eat bamboo)
Some niches are large (ie. Rats live everywhere and eat a variety of foods)

35. Competition
Organisms attempt to use the same resource in the same place at the same time
Competitive exclusion principle—no two species can occupy the same niche in the same habitat at the same time

36. Predation One organism captures and feeds on another
Predator— organism that does the killing and eating
Prey—food organism

37. Symbiosis “living together”
Any relationship in which two species live closely together is called symbiosis. This benefits at least one member of the relationship. There are three types of symbiotic relationships.

38. Mutualism
Both species benefit

39. Commensalism Relationship in which one member benefits while the
other member is unaffected.

40. Parasitism
One species benefits and the other is harmed

41. Ecological Succession
Ecosystems are constantly changing in response to natural and human disturbances.
As an ecosystem changes, older inhabitants gradually die out and new organisms move in, causing further change in the community.

42. Succession: the natural change in a community over time.
The final community where little change occurs is the climax community.

43. Types of Succession Primary--starting life in a new place
Secondary--change after a natural disaster

44. Whale-fall Community
A whale dies and sinks to the bottom of the ocean.
Tissues are eaten by scavengers.
Decomposition enriches the sediment.
Bacteria can even decompose the oils inside the whale bones!

45. World Biomes
A biome is a complex of terrestrial communities that covers a large area and is characterized by certain soil and climate conditions as well as particular plants and animals.

46. Why Can’t Polar Bears Live in the Desert?
Species vary in their adaptations to different conditions.
Adaptations are inherited characteristics that increase an organism’s ability to survive and reproduce.
Tolerance--the ability withstand changes in abiotic and biotic environmental factors

47. How is the seal adapted to its environment?
Streamlined shape.
Forward-facing eyes for clear vision ahead.
Strong teeth to catch fish.
Flippers to help it swim.
Thick layer of body fat to keep it warm.
Hind legs have evolved into a a strong rudder-like tail.

48. Weather vs. Climate Weather Climate
day to day conditions of the Earth’s atmosphere at a certain time and place
Climate
year after year conditions
along with plants and animals, defines a biome

49. TROPICAL RAINFOREST Most biologically diverse biome; warm
and wet with lush plant growth

50. GRASSLAND Savanna Covered with grasses and other small plants; summers
are hot, winters are cold, and rainfall uncertain.

51. DESERT
Arid, less than 25 cm of rain a year, almost nonexistent plant life.

52. TEMPERATE FOREST Deciduous Forest
Dominated by broad-leaved hardwood trees that
lose their foliage annually.

53. TAIGA Coniferous Forest
Conifers, warmer and wetter than tundra, long and severe winters

54. TUNDRA
Treeless, mosses and grasses, low water, cold

55. How Populations Grow Three factors can affect population size:
Number of births
Number of deaths
Number of individuals that enter or leave

56. Population Growth Birth rate > Death rate = grows
Birth rate < Death rate = shrinks
Birth rate = Death rate = stable
Immigration—movement into an area
Emigration—movement out of an area

57. Growth Patterns of Populations
Populations grow exponentially when resources are unlimited.
When resources become less available, logistic growth occurs.
Carrying capacity-the largest number of individuals that a given environment can support
Growth Patterns of Populations

58. Limiting Factors
Carrying capacity cannot be exceeded due to limiting factors.
Limiting factor--any factor that restricts the existence, numbers, reproduction, or distribution of organisms. Examples are temperature and food availability

59. Density Dependent Limiting Factors
Density-dependent factors
Competition
Predation
Parasitism
Disease

60. Predator-Prey Relationship

61. Density-Independent Limiting Factors
Unusual Weather—droughts, severe winter frost
Natural Disasters—hurricanes, fires
Seasonal Cycles— frosts, droughts, temp changes
Human Activities—dams, clear-cutting

62. Human Population Growth
Like the populations of many other living organisms, the size of the human population tends to increase with time.
In the year 2000, there were an estimated 6,078,684,329 people on Earth.
By 2050, world population may reach 9 billion!
Will science and changes in society control the possible negative impacts on the environment?

63. Demography The scientific study of human populations.
With advances in nutrition, sanitation, and medicine, people are living longer.
At first, populations grow due to lower death rates.
Demographic transition—birth rate also falls; population grows slowly then stops.

64. Demographic Transition
So far the demographic transition has happened in only a few countries.
United States
Europe
Japan
Worldwide population is still growing as most countries have not reached this point.

65. Age Structure

66. In the April 1997 issue of Women's Press the following summation was made. If we divided the world's population by 60 million there would be 100 humans, of whom:
57 are Asian
21 are Europeans
14 are Hispanics from the Western Hemisphere
8 are Africans
51 are females
70 are non-white
70 are non-Christian; 30 are Christian
6 individuals control 50%of the world's wealth--all Americans
70 are unable to read
50 suffer from malnutrition
1 is near death and 1 is about to be born
and only 1 would have a college education

67. Biodiversity Variety is the spice of life
Biodiversity is one of the Earth’s greatest natural resources.
Humans depend on other organisms for survival.
When one species is threatened, others are affected.

68. Human Threats to Biodiversity
Altering habitats
Hunting species to extinction
Introducing toxic compounds to food webs
Introducing foreign species to new environments.
Extinction—disappears from all or part of range
Endangered—populations are declining

69. Pollution Toxic compounds accumulate in the tissues of organisms.
Biological magnification—harmful substances concentrate in tissues of organisms.
Each step in the food chain contains 10x the concentration as the organisms in the step below it.

70. Biological Magnification of DDT

71. Introduced Species
Another threat to biodiversity is the introduction of invasive species, either accidentally or intentionally.
These organisms often reproduce rapidly because their new habitat lacks the parasites and predators that control them in their natural habitat.

72. Conserving Biodiversity
Captive breeding programs in zoos
Parks and reserves
Challenges
Financial hardships
International relationships