Ecological Interactions

1. Ecological Interactions

2. What is Ecology • Ecology is the interactions between various organisms and their environments. • This includes interactions between living and non living factors. • Great White Shark Video

3. Habitat • The place where an organism lives and that provides the things the organism needs is called it’s habitat. • Habitats provide food, water, shelter, and other things needed to grow and reproduce. • A specific type of habitat which a certain level of rainfall, vegetation, and communities of organisms is known as a biome. • What are some examples of biomes?

4. Biotic vs. Abiotic • Biotic Factors are the living parts of an ecosystem. They include grass, plants, seeds, and other organisms. • Abiotic Factors are the nonliving parts of an ecosystem. They include things such as water, sunlight, oxygen, soil, and temperature.

5. Groups in Ecosystems • Species: A group of organisms that are physically similar and can reproduce with each other to produce fertile offspring. • Population: All the members of one species in a particular area.

6. Groups in Ecosystems • Community: All the different populations that live together in an area. • Ecosystem: The community and abiotic factors in a specific area.

7. Changes in Population Size • Population can change in size when new members enter the population or when members leave the population. • This can occur due to births, deaths, immigration, and emigration.

8. Population Cycles • A population cycle shows the population of various organisms over time. • As Predator Populations increase they overuse their resources and prey sizes decrease. • Because there is less prey this causes predator sizes to eventually decrease. • Because predator sizes go down this causes prey sizes to increase. • As you can see this can be an endless cycle!

9. Changes in Population Size • Populations can often change due to limiting factors. • A limiting factor is an environmental factor that prevents a population from increasing. • Some limiting factors for populations are food, space, and weather conditions.

10. Human Population Graph Human Population Clock

11. Limiting Factors • Limiting Factors: These factors are things that cause a population to stop increasing or to go down. • What are some examples of limiting factors? • Examples of limiting factors would be things such as water, food, to many predators, oxygen (air), climate (heat/cold), natural disasters, space etc.

12. Natural Selection • The changes that make organisms better suited to their environments develop through a process called Natural Selection. • Individuals in a population have different characteristics. Those individuals whose characteristics are best suited for their environment tend to survive and produce offspring. • Online Adaptation Tool

13. Natural Selection Continued… • Over many generations individuals with those characteristics continue to reproduce. Individuals that are poorly suited to the environment are less likely to survive and reproduce. • This process results in adaptations, behaviors and physical characteristics of species that allow them to successfully live in their environments. • Natural Selection Video for 3 Organisms

14. Key Points to Natural Selection • 1. All individuals of any given species are different because of their DNA from their parents. • 2. If those differences help you survive you can reproduce. • 3. After reproduction you have offspring with similar characteristics that help them survive. • 4. This same pattern continues generation after generation. Whatever organism has the best characteristics most suited to their environment survives. • 5. Natural selection over time helps organisms develop adaptations which help them survive in their individual environment.

15. Adaptations • Every organisms has a variety of adaptations that are suited to its specific living conditions. • Adaptations are the traits that help you survive in your environment. • Frozen Frogs • Leaf Mantis

16. Are adaptations always advantageous? • Not all adaptations are necessarily advantageous or beneficial to have. • In fact most adaptations do not influence the survival of an organism. • Sometimes organisms have old adaptations that used to be beneficial but no longer serve any purpose. • Any organ or part that is no longer useful is known as a vestigial organ.

17. Are adaptations always advantageous? • For example humans have an appendix that used to be part of their digestive system but no longer serves a purpose. • Whales have pelvic bones that serve no purpose. • The wings of ostriches are vestigial because they are to heavy to fly. • The eyes of certain cave fish are vestigial because they no longer can use them to see.

18. Peppered Moth Story • Back around 1850 in England there existed two different types of moths that came in light and dark forms. • Pollution from the Industrial Revolution darkened the tree trunks where the moths inhabited.

19. Peppered Moth Story • The lighter moths which used to be well camouflaged were now easily seen by birds that would eat them. • The dark colored moths now had a characteristic which helped them survive in their environment because they could not be seen on the dark tree trunks.

20. Is Being Dark Always an Advantage for Moths • It’s important to realize that an adaptation is not always beneficial in every environment. • Can you think of an environment where it would not be beneficial to be a dark colored moth?

21. Galapagos Finches • The Galapagos Islands are a group of islands located off the coast of South America. • There are different dominant bird species on almost every island. Why? • The food available on each island differs in size. The bird with the beak best suited to eat the food usually survives.

22. Galapagos Finches • Some beaks are advantageous to have on certain islands but not others. • Organisms that are able to eat usually are able to grow up and reproduce. • This is Survival of the Fittest.

23. So what’s the best Beak?

24. How do we use genetics to benefit us? • Dairy Farmers sometimes only breed the cows that produce the best milk. Over time the milk product is better because only the best cows are reproducing. • “Pumpkin Story”

25. How do animal in nature use this? • Some insects use mimicry to make themselves look like a dangerous creature, even though they are really not. • Example: The picture to the right is not a wasp. It is actually a moth. Some people call it a hornet moth because of it’s appearance. • Animals such as this that are naturally different can use this as an advantage and survive. Insects can not decide when to use mimicry but if they naturally have traits that help them survive they will pass them on to their offspring.

26. How do animal in nature use this? • Hollow structure of hair helps insulates animals from hot and cold weather. • It allows animals that are always outside to be able to deal with local conditions. • Wooly Bear Caterpillar Video Frozen Planet (24:00-27:40)

27. Organs Structures • The structure of an organisms organs can often help it survive in a specific environment. • Birds have hollow bones which allow them to fly in air. • Dense root structures allow plants to grow in compact arid soil.

28. Inherited vs. Acquired • All of these characteristics we have discussed are inherited. That means they are passed on from parent to offspring. • Acquired characteristics are just the opposite. They are acquired during the life of the organism and not passed on to their offspring. Just because your Dad was really good at football doesn’t mean you will be. He acquired that trait.

29. Inherited vs. Acquired • Examples of Inherited Characteristics could be: Eye Color, Hair Color, Height, Color Blindness, Diseases, Face Shape, being Bald, etc. • Examples of Acquired Characteristics could be: Sports Skills, Education, Muscle Mass, etc.

30. Short Term Adaptations • Adaptations that occur within the lifetime of the organisms are known as stimulus-response changes. • For example when plants bend towards the sunlight this is a short term adaptation known as phototropism.

31. Organism Interactions • There are 3 main types of interactions among organisms. They are competition, predation, and symbiosis.

32. Competition • Different species can share the same habitat. Different species can also share similar food requirements. • For example Lions and Hyenas are both flesh eaters that live in the Serengeti. They must constantly compete for limited resources. • Mudskippers Video Competition • Penguin Thieves

33. Predation • An interaction in which one organism kills and eats another is called predation. The organism that does the killing is the predator. The one that is killed is the prey. • Komodo Dragon Video

34. Predator Adaptations • Predators have adaptations that help them catch and kill their prey. • For example a cheetah can run very fast for a short time, enabling it to catch its prey.

35. Prey Adaptations • Remember the Peppered Moth. That is an example of prey adaptations. • Other examples are protective coverings such as the quills a porcupine has.

36. Symbiosis • Symbiosis is a close relationship between two or more species wherein one of them benefits! • Ant Symbiosis

37. Symbiosis-Mutualism • A relationship in which both species benefit is called mutualism. • At this very moment you are participating in a mutualistic relationship. Bacteria called Escherichia coli in your stomach. They help you digest foods that mammals can not normally digest and you give them a place to live.

38. Symbiosis Pictures

39. Symbiosis-Commensalism • Commensalism is a relationship in which one species benefits and the other species is neither helped nor harmed. • Least common type of symbiosis • Red Tailed Hawk can build it’s nest in a cactus. The hawk gets shelter but the cactus gets no benefit. • Commensalism Video

40. Symbiosis-Parasitism • Parasitism involves one organism living on or inside another organism and harming it. • Common parasites are ticks and leeches. These parasites have adaptations that enable them to attach to their host and feed on its blood. • Unlike a predator, a parasite does not usually kill the organism it feeds on. • Bird Parasitism Video

41. Energy Roles in Ecosystems • An organisms energy role in an ecosystem may be that of a producer, consumer, or decomposer. • Most energy is introduced through the sun into the ecosystem.

42. Producers • Energy first enters most ecosystems as sunlight. Some organisms such as plants, algae, and some bacteria, are able to capture the energy of sunlight and store it as food energy. • An organism that can make its own food is a producer. Producers are the source of all the food in an ecosystem. • Photosynthesis: Using Sunlight + CO2 + H20 = O2 + Sugar (Glucose)

43. Archaebacteria-Producers • Some Archaebacteria can produce food from gas and hydrogen sulfide. • They are often found in deep sea vents, geysers, or under ground. • Archaebacteria are now part of the Kingdom Monera.

44. Consumers • Consumers are organisms that obtain energy by feeding on other organisms. • Consumers are classified by what they eat. • Consumers that eat only plants are called herbivores. (Deer and Cattle) • Consumers that eat only animals are called carnivores. (Lions, Spiders, Snakes) • Consumers that eat both plants and animals are called omnivores. (Example: Crows, Humans)

45. Cellular Respiration Most animals perform a process called cellular respiration. Cellular respiration involves getting energy from food and exchanging oxygen and carbon dioxide with the atmosphere. Similar to how plants use photosynthesis to get energy we use cellular respiration to get energy from food.

46. Decomposers • Organisms that break down wastes and dead organisms and return the raw materials to the environment are called decomposers. (Bacteria, Fungi, Mushrooms, Mold) • Without Decomposers their would be no energy cycle because they return materials such as carbon and nitrogen back to the soil where plants can use them