1. January-October 2014 temperatures highest on record November 29, 2014
The global average temperature over land and ocean surfaces for January to October 2014 was the highest on record, according to NOAA. October was the hottest since records began in 1880.

2. Politics, not severe weather, drive global-warming views December 1, 2014
Scientists have presented the most comprehensive evidence to date that climate extremes such as droughts and record temperatures are failing to change people's minds about global warming.
"Our results show that politics has the most important effect on perceptions of climate change."
Some previous studies suggested temperature patterns do, in fact, influence perceptions about global warming, but none measured climatic conditions as comprehensively as the current investigation. Past research often considers a two-day window or a particular community and a single measure of temperature, not an expansive sweep of multiple climate measures as the authors of this study do.
The study analyzed climatic storm-severity measures used by NOAA -- temperature, drought, precipitation and wind velocity -- from all 50 states in combination with the 11 years of public opinion data. "This gives us the pulse of the nation," said Marquart-Pyatt.
While advocates of global warming reduction efforts hope that experience with a changing climate will eventually convince the public of the reality and seriousness of the problem, the current findings do not bode well for that scenario.
Given this expansive treatment of the issue, there is "little grounds for optimism," the study says, "that public concern about climate change will be driven by future climatic conditions."

3. Age structure for the males in a population of large cactus finches on one of the Galápagos Islands in 1987. 11 10 9 8 7
Age (years) 6 5
Figure 19.3 Age structure for the males in a population of large cactus finches (inset) on one of the Galápagos Islands in 1987. 4 3 2 2 1 10 20 30 40 50
Percent of population
Figure 19.3

4. Chapter 41
Community Ecology

5. 41.1 What Factors Affect Community Structure?
The type of place where a species normally lives is its habitat, and all species living in a habitat constitute a community
Communities often are nested one inside another

6. What Factors Affect Community Structure?
Community structure can change:
As the community forms and ages
As a result of natural or human-induced disturbances
With changes in physical factors such as climate and resource availability
Due to various types of species interactions

7. What Factors Affect Community Structure?
Species interactions can be mutually beneficial, mutually harmful, or benefit one species while harming the other
Example: Commensal ferns attached to the trunk of a tree; the fern benefits from the light, and the tree is unaffected

8. What Factors Affect Community Structure?
Symbiosis
“Living together”
A relationship in which two species have a prolonged close association
Two species that interact closely for generations can coevolve – each species acts as a selective agent on the other
Can be a commensal, mutualistic, or parasitic relationship

9. 41.2 How Do Species Cooperate?
In a mutualistic interaction, two species benefit by taking advantage of one another
Example: pollinators eat nectar and pollen, and plants receive pollen from other plants of the same species
+ / +

10. How Do Species Cooperate?
For some mutualists, the main benefit is defense
Example: Sea anemone and anemone fish
An anemone fish has a mucus layer that shields it from stinging cells (nematocysts) of a sea anemone
Tentacles of the anemone protect the fish from predators
The anemone fish chases away the few fishes that are able to eat sea anemone tentacles

11. How Do Species Cooperate?
Figure Mutualism between a sea anemone and a pink anemone fish. The tiny but aggressive fish chases away predatory butterfly fishes that would like to bite off tips of the anemone’s stinging tentacles. The fish cannot survive and reproduce without the protection of an anemone. The anemone does not need a fish to protect it, but it does better with one.

12. Mutualistic relationship + / +
Commensal relationship + / 0
Parasitic relationship + / -

13. 41.3 How Do Species Compete?
Resources are limited and individuals of different species often compete for access to them (interspecific competition)
Competition adversely affects both species

14. How Do Species Compete?
Each species has an ecological niche defined by physical and biological factors; the more similar the niches of two species are, the more intensely they will compete
An animal’s niches include the temperature range it can tolerate, species it eats, and places it can breed
A flowering plant’s niche would include its soil, water, light, and pollinator requirements

15. How Do Species Compete?
Two Paramecium species compete for the same food (bacteria)
Each species thrives when grown alone
When grown together, P. aurelia drove P. caudatum to extinction

16. Relative population densityLM
Separate
cultures
Relative population density
Paramecium aurelia
Combined
cultures 2 4 6 8 10 12 14 16 LM
Figure 20.8 Competitive exclusion in laboratoy populations of Paramecium
Days
P. aurelia
P. caudatum
Paramecium caudatum
Figure 20.8

17. 41.4 How Do Predators and Their Prey Interact?
Predation
One species (the predator) captures, kills, and eats another species (the prey)

18. How Do Predators and Their Prey Interact?
Predator and prey exert selection pressure on one another
Predators exert selection pressure that favors improved prey defenses
Improved prey defenses in turn exert selection pressure on predators to improve capture skills, and so on

19. How Do Predators and Their Prey Interact?
Figure 41.6 Graph of the number of Canadian lynx (dashed line) and snowshoe hares (solid line), based on counts of pelts sold by trappers
to Hudson’s Bay Company during a ninety-year period.

20. How Do Predators and Their Prey Interact?
Defensive adaptations of prey
Hard or sharp parts that make prey difficult to eat
Chemicals that taste bad or sicken predators
Tricking or startling an attacking predator
Warning coloration that predators learn to avoid, such as the black and yellow stripes of stinging wasps and bees

21. How Do Predators and Their Prey Interact?
In a type of mimicry, prey masquerade as a species that has a defense that they lack
Example: some flies that can’t sting resemble stinging bees or wasps
Mimicry
A species evolves traits that make it more similar in appearance to another species

22. How Do Predators and Their Prey Interact?
A Wasp that can inflict a painful sting. Like many stinging bees and
wasps, it has a yellow and black pattern.
Figure 41.7 Mimicry.
B Fly, which lacks a stinger, mimics
the color pattern of stinging insects.

23. Figure 20.12 Mimicry in snakes
Milk Snake Coral Snake
Figure 20.12

24. How Do Predators and Their Prey Interact?
Predator adaptations include sharp teeth and claws
Predators and prey may be coevolved for speed
Example: cheetah and gazelle
Both predators and prey use camouflage (a form, patterning, color, or behavior that allows them to blend into their surroundings) to avoid detection

25. How Do Predators and Their Prey Interact?
Figure 41.8 Camouflage
A Frilly pink body parts of a flower mantis help hide it from insect
prey attracted to the real flowers.
B Fleshy protrusions give a scorpionfish the appearance of an
algae-covered rock. Fish that come close for a nibble end up as prey. A B

26. How Do Predators and Their Prey Interact?
Herbivory
An animal feeds on plant parts
The number and type of plants in a community can influence the number and type of herbivores present

27. How Do Predators and Their Prey Interact?
Two types of defenses against herbivory
Withstand and recover quickly
Traits such as spines, tough leaves, or toxins that deter herbivory
Plant defenses favor adaptations in herbivores
Example: Koalas have special enzymes to break down toxins in eucalyptus

28. 41.5 How Do Parasites and Their Hosts Interact?
Parasitism
One species (the parasite) feeds on another (the host), without immediately killing it
Endoparasites live and feed inside their host
Ectoparasites feed while attached to a host’s external surface

29. How Do Parasites and Their Hosts Interact?B
Figure Parasites inside and out
A Endoparasitic roundworms in the intestine of a host pig.
B Ectoparasitic ticks attached to and sucking blood from a finch.
C Ectoparasitic dodder (Cuscuta), also known as strangleweed or devil’s hair. This parasitic flowering plant has almost no chlorophyll. Leafless stems wrap around a host plant, and modified roots absorb water and nutrients from the host plant’s vascular tissue. C

30. How Do Parasites and Their Hosts Interact?
Parasitoids
An insect that lays eggs in another insect, and whose young devour their host from the inside
Reduce a host population in two ways:
Parasitoid larvae withdraw nutrients and prevent the host from reproducing
Presence of larvae leads to death of the host
As many as 15% of all insects may be parasitoids

31. How Do Parasites and Their Hosts Interact?
Biological pest control
Parasites and parasitoids are commercially raised and released in target areas as biological control agents – an environmentally friendly alternative to pesticides
A biological control agent must be adapted to a specific host species
Introducing a biological control species into a community is risky – they sometimes go after nontargeted species

32. How Do Parasites and Their Hosts Interact?
Figure Biological pest control. A commercially raised parasitoid wasp about to deposit a fertilized egg in an aphid. This wasp is used to reduce aphid populations. After the egg hatches, a wasp larva devours the aphid from the inside.

33. 41.6 How Do Communities Change Over Time?
Pioneer species
Species that can colonize a new habitat
Mosses, lichens, and some flowering annuals
Species often alter the habitat in ways that allow other species to replace them (ecological succession)
First, opportunistic colonizers of new or newly vacated habitats are pioneer species, which have high dispersal rates, grow and mature fast, and produce many offspring

34. How Do Communities Change Over Time?
Seeds of later species grow in mats of pioneers
Organic wastes and remains accumulate and help other species take hold
Later successional species often shade and eventually displace earlier ones

35. Figure 20.23 Primary succession under way on a lava flow in Valley of Fires State Park, New Mexico

37. How Do Communities Change Over Time?
Secondary succession
A new community develops in a site where the soil that supported an old community remains
In secondary succession, a disturbed area within a community recovers.
Occurs in abandoned agricultural fields and burned forests

38. How Do Communities Change Over Time?
Species composition of a community changes frequently, and unpredictably
Random events can determine the order in which species arrive, and affect the course of succession
Example: 1980 eruption of Mount Saint Helens
Presence of some pioneers helped later-arriving plants become established
Other pioneers kept the same late arrivals out

39. How Do Communities Change Over Time?
Indicator species are the first to do poorly when conditions change, so they can provide an early warning of environmental degradation
Example: trout are highly sensitive to pollutants and cannot tolerate low oxygen levels

40. 41.7 How Can A Single Species Alter Community Structure?
Keystone species
A species that has a disproportionately large effect on community structure
Loss or addition of even one species (keystone species) may destabilize the number and abundances of species in a community

41. How Can A Single Species Alter Community Structure?
Experiment: sea stars in a rocky intertidal zone in California
Sea stars prey mainly on mussels and were removed from experimental plots
Mussels then crowded out seven other species of invertebrates
Conclusion: sea stars are a keystone species
Normally keep number of prey species high by preventing competitive exclusion by mussels

42. How Can A Single Species Alter Community Structure? (cont’d.)
Figure Effect of removal of the sea star Pisaster on the number of species in tide pools. Sea stars were not removed from control plots.

43. Keystone species – Grey Wolf
1995: reintroduced; 2009: 116 wolves in park
Prey on elk and push them to a higher elevation
Regrowth of aspen, cottonwoods, and willows
More beaver dams, more wetlands, more aspens
Reduced the number of coyotes
Fewer attacks on cattle
More smaller mammals

44. How Can A Single Species Alter Community Structure?
Exotic species
A species that evolved in one community and later became established in a different one
Can dramatically alter a natural community
More than 4, ,000 exotic species have become established in the United States
Visit the National Invasive Species Information Center at

45. How Can A Single Species Alter Community Structure?
Figure Three exotic species that are altering natural communities in the United States. To learn more about invasive species in the United States, visit the National Invasive Species Information Center online at

46. How Can A Single Species Alter Community Structure?
Kudzu native to Asia: overgrowing trees across the southeastern United States
Gypsy moths native to Europe and Asia: feed on oaks through much of the United States
Nutrias native to South America: abundant in freshwater marshes of the Gulf States

47. 41.9 Fighting Foreign Fire Ants
Red imported fire ants, Solenopsis invicta, have a venomous sting and disrupt native wildlife communities
Pesticides do not control spread
Biological control involves phorid flies – the larvae eats its way through the fire ant and undergoes metamorphosis in its head
Global climate change is expected to help RIFAs extend their range in the U.S.

48. Figure 19.6a Logistic growth of a seal population

49. Breeding male fur seals10 8
Breeding male fur seals
(thousands) 6 4 2
Figure 19.6 Logistic growth of a seal population
1915
1925
1935
1945
Year
Figure 19.6

50. Density (beetles/0.5 g flour)
100 80 60
Survivors (%) 40 20
Figure 19.8b Density-dependent regulation of population growth 20 40 60 80
100
120
Density (beetles/0.5 g flour)
(b) Decreasing survival rates with increasing density in a
population of flour beetles
Figure 19.8b

51. Number of breeding pairs12 11 10
Average clutch size 9 8
Figure 19.8a Density-dependent regulation of population growth 10 20 30 40 50 60 70 80 90
Number of breeding pairs
(a) Decreasing birth rate with increasing density in a
population of great tits
Figure 19.8a

52. 41.8 How Many Species Will A Community Hold?
Equilibrium model of island biogeography
The number of species living on any island reflects a balance between immigration rates for new species and extinction rates for established ones
Colonization rates depend on the distance between an island and a mainland source of colonists (distance effect)
An island’s size affects species richness (area effect)

53. How Many Species Will A Community Hold?
Figure Vascular plant colonization of Surtsey, a volcanic island shown forming in the inset photo. Seagulls first began nesting on the island in 1986.

54. 11/26 Friday Schedule Populations 40 11/28 No Class 12/3
Ecology Succession 41
12/5
Trophic Levels
Lab Review 42
12/10
Biomes & Human Effect
43&44
12/12
Lecture Review
Lab Final Exam
12/17
Final Exam
12/19
Make up class if needed