Behaviors in Communities. Nature s predictable patterns

Transcription

1 Behaviors in Communities Nature s predictable patterns

2 2. What patterns exist in communities and ecosystems?

3 How does the ecosystem s physical environment influence patterns?

4 We know ecosystems are shaped by: biotic factors food supply vectors demographic events abiotic factors climate/weather space Rainfall Soil air catastrophic events

5 Can these factors influence the behavior of populations in the ecosystem? Do these influences create predictable patterns?

6 Patterns in growth

7 Some organisms life cycles are influenced by temp/ light patterns.

8 Diurnal and Nocturnal

9 What behaviors are influenced by this pattern?

10 The Cactus Ferruginous Pygmy Owl is a keystone species. Predatory birds and foxes would die off with the absence of the cactus pygmy owl.

11 Tidal influences on populations in communities

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13 ECOLOGICAL SUCCESSION Predictable and orderly observed process of change in the populations, composition and structure of an ecological community over time.

14 Impact of a species on its own environment. Sudden change in the conditions of the environment

15 Ecological succession is a force of nature. Ecosystems, because of the internal species dynamics and external forces, are in a constant process of change and re-structuring.

16 Succession may be initiated either by formation of new, unoccupied habitat (e.g., a lava flow or a severe landslide) or by some form of disturbance (e.g. fire, severe wind, logging) of an existing community.

17 Succession when the conditions of an environment suddenly and drastically change. Primary succession

18 Primary succession - occurs on an area of newly exposed rock or sand or lava or any area that has not been occupied previously by a living (biotic) community.

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20 Pioneering species

21 builds humus

22 Succession when the conditions of an environment change less dramatically. Secondary succession

23 Secondary succession - takes place where a community has been removed, e.g., in a plowed field or a clear cut forest but some remnants of a community remains (not starting from scratch )

24 Does ecological succession ever stop? There is a concept in ecological succession called the "climax" community. The climax community represents a stable end product of the successional sequence. In the climate and landscape region of the Olympic National forest ecosystem, for example, this climax community is the Coniferous Forest" subdivision of the Boreal Biome.

25 Another cause of ecosystem change - the impact established species have on their own environments. A consequence of living is the subtle and sometimes overt alteration of one's own environment. The original environment may have been optimal for the first species of plant or animal, but the newly altered environment is often optimal for some other species of plant or animal. Under the changed conditions of the environment, the previously dominant species may fail and another species may become ascendant.

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27 Do you think there is a pattern (expected behavior) in a population s response to changes in their environment? Plant and animal behaviors can be understood as responses to changes in their environments.

28 What behaviors could be expected in response to a increase in temperature? sweat seek shelter pant move to a cooler place Wear fewer clothes

29 What behaviors could be expected in response to a drop in temperature? Seek shelter Huddle with others Eat more food for more internal heat Put on more clothes migrate

30 Animals adapt Humans can invent

31 Storing for the winter Squirrels, chipmunks, and some jays often store large supplies of food (such as nuts and seeds) in the ground, under fallen leaves, or in tree hollows for use during the cold winters when food is scarce. Cold temperatures help prevent the decomposition of the nuts and seeds.

32 Freezing North American Wood Frogs

33 Tolerance Every species has a set of environmental conditions under which it will grow and reproduce most optimally.

34 As long as the ecosystem's set of environmental conditions remains constant, those species optimally adapted to those conditions will flourish. Disturbances in the ecosystem can disrupt the community and cause significant changes in its composition.

35 In any community some species may become less abundant over a time interval, or they may even vanish from the ecosystem altogether. Similarly, other species may become more abundant, or new species may even invade into the community from adjacent ecosystems. Invasive, nonnative plants (Scotch broom) or large fires in a forest

36 Behaviors can be understood as a response to a stimulus* What are some examples of biotic changes in the environment that might serve as a stimulus for an animal to change its behavior? * A cue detectable change from the environment

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39 Changes in abundance of food source new predators moving in Availability of water Habitat alteration

40 Behavioral responses that are predictable because they are in response to predictable/cyclical patterns in the environment become genetically programmed. physical

41 Do you think there is a predictable pattern to behavior in response to specific stimulus? Animals adopt different behaviors to respond to environmental stimuli. Cyclical stimuli = cyclical behaviors.

42 The White-tailed Jack rabbit turn from brown to white in the fall and from white to brown in the spring. The white coat helps the hare hide in the snow. In spring, the hare loses the white fur. It grows back each fall. They have three layers of fur... inside layer - thick, dark brown second layer - longer fur, lighter brown outer layer - longest fur, white in color, covers the brown layers.

43 hibernation When animals adapt to the cold weather by going into a deep sleep to survive the winter without food. An animal in this state expends little metabolic energy.

44 Hibernation is a time when a mammal lowers its rate of metabolism and lives in a state of stillness. Rather than migrating, they find a safe, warm place to hole up and spend the winter months.

45 Animals get energy by consuming food; because there is less food available in the winter, animals enter hibernation to conserve energy and to survive the winter. In the late summer and fall, before going into hibernation, animals eat a lot of food. Their bodies are able to live off the stored body fat.

46 Hibernation is different from sleep. With normal sleep, the animal moves a little, has an active brain, and can wake up very quickly. A true" hibernator appears to be dead because the animal's heart rate slows down and the body temperature drops to almost the same temperature as outside. The animal's respiration also slows down. It takes a long time for the animal to wake up and to move again.

47 Animals that hibernate put on a specialized type of fat, called brown fat. This fat is found across the back and shoulders of hibernating animals, close to an animal's organs (brain, liver). Brown fat works fast to deliver quick energy to an animal coming out of hibernation.

48 Who Hibernates? Ground squirrels, Woodchucks, prairie dogs, tortoises, bees, snails etc. usually go to sleep in early December and come awake in early March

49 Torpor a temporary sleep condition in which body temperatures drop and heart rate and breathing slow drastically nighthawk With torpor, the animal doesn t seem to see, hear, or feel things going on around it. It is groggy and it takes a little while for it to wake up. This is not as deep a sleep as hibernation and can last a very short time.

50 Hibernation or Torpor? Some hibernating animals wake up and move around, have a snack when the temperature is a little warmer, and then go back into hibernation again.

51 The Richardson's Ground Squirrels store some food. During winter, they wake up every 10 to 14 days and have a snack.

52 Skunks, raccoons, opossums are also in this family. These animals breathe a little more slowly and lower their body temperature a few degrees while sleeping, but they wake up to forage between winter snows.

53 When temperatures increase at the beginning of spring, the animals wake up. Scientists believe that animals use temperature and amount of daylight to dictate when to begin eating and when to go into hibernation.

54 Migration when animals move from one place to another as a result of temperature changes Animals migrate for different reasons: to find a better climate (better weather) to find better food to find a safe place to live to find a safe place to raise their young A common response to changing environmental conditions

55 salmon, humpback whales, Canada geese, monarch butterflies, elk Many geese and other birds migrate thousands of miles. Some travel over 7,000 miles one way! Some may travel up to 1000 miles without even a rest stop.

56 ave. weight = 3.3 g only 3 ½ inches long

57 Hummingbirds have very special features Their tongues are so long, they wrap around their skull inside their head They can see ultraviolet light humans and most other animals cannot. They are the only bird that can fly backward and hover.

58 Resting heart beat is 480 beats per minute Have to feed about every minutes all day long to maintain enough food for the energy their bodies need (about 35 calories a minute) Largest brain compared to its size of all birds

59 Diurnal Torpor to survive cold nights but when fall comes The Rufous has the longest migration route of all US hummingbirds more than 5,000 miles a year! The Rufous migrates alone.

60 Why don't birds get lost? Some birds fly at night and use the stars to help them. Birds that fly during the day use the position of the sun as a guide. Waterfowl follow rivers. Hawks and eagles follow mountain ranges. Scientists cannot fully explain how birds find their way.

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62 What was the stimulus for these migrations? While the seasons stimulated the migration behavior what specific factors might have been causing the animals to migrate? Hint: what might the animals be looking for in the new area?

63 spring

64 What stimulus triggers the migration? One challenge all cold blooded (ectothermic**) animals (monarch insects) encounter as they try to maintain homeostasis is temperature control. migrate alter their metabolism **Get their heat from their environment only some winter over, or winter over in life stage other than adult

65 a) The reason for the migration b) The stimulus that prompts the animal s migratory behavior.

66 Why might animals migrate north Arctic Circle for the summer? Gray whale

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68 On a smaller scale, animals continually make choices in response to changing environmental conditions.

69 environment Behavior is an animal s response to sensory input. other animals or

70 Orientation behavior Places the animal in its most favorable environment. taxis or kinesis deliberate/directional random movement movement toward or away

71 Phylum, Arthropoda; Class, Malacostraca; Order, Isopoda

72 Design an experiment to test an animal s environmental preference. Is the behavior taxis or kinesis? Test the animal s environmental preference compared to a control group. Choose the variable to test. Construct a test environment. Conduct a controlled experiment. Evaluate/conclude.

73 Variables: Temperature substrate Light Moisture Acidity/basidity

74 1. Discuss your research with your research partner. 2. Select the variable to test. 3. [check with Mrs. Whitt] 4. Write up a research question and hypothesis. 5. Define the materials you plan to use and write a preliminary procedure. 6. [check with Mrs. Whitt] 7. Pre-lab write up: Purpose and Hypothesis Material and methods