1. What is Ecology? 1. “The scientific study of the interactions between organisms and their environments is called ecology.”

2. 2. “The trouble with ecology is that you never know where to start because everything affects everything else.”

3. 3. “Ecologists often face extraordinary challenges in their research because of the complexity of their questions, the diversity of their subjects, and the large expanses of time and space over which studies must often be conducted. Ecology is also challenging because of its multidisciplinary nature; ecological questions form a continuum with those from other areas of biology, including genetics, evolution, physiology, and behavior, as well as those from other sciences, such as chemistry, physics, geology, and meteorology.”

4. 4. “Ecology concerns itself with the interrelationships of living organisms, plant or animal, and their environments; these are studied with a view to discovering the principles which govern the relationships.”

5. What is Ecology? 5. “In other words, understanding ecology requires understanding everything else there is to know about biology, and then some. It’s probably the easiest part of Biology to recognize and the hardest part to really understand.”

6. Assignment #1: Give your own definition of Ecology

7. Ecosystems: Food chains, Food webs and Food pyramids TAKS Objective 3 TEKS 12 E

8. Gotta get cha eat on! Many of the relationships between living organisms in an ecosystem have to do with food.

9. Energy is passed from one to another!

10. Scientists use graphic representations to show food relationships and energy transfer in an ecosystem 3 Graphic Representations: 3 Graphic Representations: 1) Food Chains 2) Food Webs 3) Pyramids – three types a. Energy b. Numbers c. Biomass

11. Assignment #2: Draw your own food chain Remember: Arrows show the flow of energy Arrows point to the thing that eats

12. Autotrophs make their own food Heterotrophs eat autotrophs Autotrophs = Producers Herbivores = Primary Consumers Carnivores = Secondary, tertiary, etc. consumers Decomposers are always the final consumers

13. Assignment #3: Draw another food chain Label the Producer (the autotroph) Primary Consumer Secondary Consumer Tertiary Consumer Decomposer (final consumer)

14. Food chains show the flow of energy through an ecosystem

15. Food Chain: an example Grass → Grasshopper → Toad → Snake → Hawk → Bacterial decay Arrows show the flow of energy Arrows point to the thing that eats

16. Food Chain

17. Food Webs: many interconnected food chains; link of all food chains in an ecosystem

18. Assignment #4: Why is a food web more realistic than a food chain?

19. Types of Symbiosis MutualismCommensalismParasitism

20. Trophic Levels Each step in a food chain or food web is called a trophic level. Each step in a food chain or food web is called a trophic level. 1 st Trophic Level – producers 1 st Trophic Level – producers 2 nd+ Trophic Level – consumers (primary, secondary, tertiary, etc.) 2 nd+ Trophic Level – consumers (primary, secondary, tertiary, etc.) Each consumer depends on the trophic level below it for energy; only 10% of energy goes on to the next trophic level! Each consumer depends on the trophic level below it for energy; only 10% of energy goes on to the next trophic level!

21. Pyramids show changes in either energy or numbers or mass 1. Energy pyramids: change in energy from trophic level to the next; only 10% passes up to next level. 2. Numbers pyramids: change in number of individuals at each trophic level. 3. Biomass pyramids: change in dry weight (biomass) from trophic level to the next.

22. Top Level Consumer Primary Consumer Producer Pyramid of numbers

23. Top Level Consumer Primary Consumer Producer Last Assignment #5: Draw your own ecological pyramid

24. Question Animal Length of digestive system Diet category Animal weight Koala 305 cm herbivore 10 kg Dog 135 cm carnivore 11 kg Rabbit 272 cm herbivore 9 kg Bobcat 145 cm carnivore 12 kg 1.The table shows data about several herbivores and carnivores. Based on the data, what conclusion can you draw from the data? 1.The table shows data about several herbivores and carnivores. Based on the data, what conclusion can you draw from the data? a. There is no correlation between diet and length of digestive system. a. There is no correlation between diet and length of digestive system. b. Herbivores have longer digestive systems than carnivores. b. Herbivores have longer digestive systems than carnivores. c. Carnivores have longer digestive systems than herbivores. c. Carnivores have longer digestive systems than herbivores. d. The length of the digestive system is related to the weight of an animal. d. The length of the digestive system is related to the weight of an animal.