Presentation is loading. Please wait.

Presentation is loading. Please wait.

Adaptations to the Physical Environment

Published byWesley Ellis Modified over 8 years ago

Similar presentations

Presentation on theme: "Adaptations to the Physical Environment"— Presentation transcript:

1 Adaptations to the Physical Environment
Chapter 3 Ecology: Evolution, Application, Integration Ecology: Evolution, Application, Integration                                       David T. Krohne                                Copyright © 2015 Oxford University Press

2 Concepts 3.1 How Do Environmental Factors Limit Growth and Survival?
3.2 What Adaptations Avoid Harsh Conditions? 3.3 How Do Physiological Adaptations Alter the Organism’s Tolerance Limits? Ecology: Evolution, Application, Integration                                       David T. Krohne                                Copyright © 2015 Oxford University Press

3 How Do Environmental Factors Limit Growth and Survival?
Physical resources The inorganic materials or energy organisms require for existence Physical (abiotic) factors Physical conditions that affect growth and survival Ecology: Evolution, Application, Integration                                       David T. Krohne                                Copyright © 2015 Oxford University Press

4 How Do Environmental Factors Limit Growth and Survival?
Physical resources The inorganic materials or energy organisms require for existence Physical (abiotic) factors Physical conditions that affect growth and survival Ecology: Evolution, Application, Integration                                       David T. Krohne                                Copyright © 2015 Oxford University Press

5 Shelford’s Law of Tolerance (1913)
There are upper and lower limits to the physical factors an organism can tolerate. Ecology: Evolution, Application, Integration                                       David T. Krohne                                Copyright © 2015 Oxford University Press

6 Shelford’s Law of Tolerance
Species differ in the factors that limit their growth and in their ranges of tolerance. Deleterious effects that occur outside the range of tolerance depend on the specific physical factor. Beyond the tolerance limits, organism’s fitness is compromised. Often associated with an organism’s inability to maintain homeostasis Ecology: Evolution, Application, Integration                                       David T. Krohne                                Copyright © 2015 Oxford University Press

7 Role of Evolution In Shaping The Tolerance Curves
This tolerance curve represents the tolerance limit of the entire population. The tolerance curves of individuals vary and some of this variation is genetically determined. What implications does this have for evolution? Ecology: Evolution, Application, Integration                                       David T. Krohne                                Copyright © 2015 Oxford University Press

8 Role of Evolution In Shaping The Tolerance Curves
If the environment changes, some individuals may be better able to tolerate the new range of conditions. If these differences have genetic basis, they will be selected for. Directional selection shifts the population tolerance limit. Ecology: Evolution, Application, Integration                                       David T. Krohne                                Copyright © 2015 Oxford University Press

9 Environmental Conditions Change in Time
Some temporal variability is predictable (blue line) Seasonal Diurnal Tidal Environmental conditions can also change unpredictably (orange line) Temporal variation in the physical environment poses a significant challenge to the organism’s fitness. It is much simpler to adapt to a constant environment than to a variable one. Ecology: Evolution, Application, Integration                                       David T. Krohne                                Copyright © 2015 Oxford University Press

10 The Principle of Allocation
Adaptations to one challenge may preclude or reduce adaptations to others (Levins, 1968) Adaptation involves evolutionary trade-offs There are costs and benefits to every adaptive solution Ecology: Evolution, Application, Integration                                       David T. Krohne                                Copyright © 2015 Oxford University Press

11 Two Categories Of Adaptive Responses
Avoidance Behavioral avoidance Migration Metabolic avoidance Metabolic rate depression Hibernation Estivation Adaptations Traits that match the organism’s tolerance limits to the physical conditions it faces Behavioral Morphological Physiological Biochemical Ecology: Evolution, Application, Integration                                       David T. Krohne                                Copyright © 2015 Oxford University Press

12 Avoidance Adaptations Metabolic Avoidance
Dormancy Seeds Spores In some unpredictable habitats, dormancy can be indeterminate (until the conditions improve). Metabolic arrest For example, brine shrimp, water bears (tardigrades), rotifers Slows down the biological clock Ecology: Evolution, Application, Integration                                       David T. Krohne                                Copyright © 2015 Oxford University Press

13 Avoidance Adaptations Metabolic Avoidance
Torpor Usually in response to cold and food deficiency E.g., hummingbirds Prolonged torpor=Hibernation E.g., bears, ground squirrels Estivation Usually in response to drought and heat E.g., snails Slows down the biological clock Ecology: Evolution, Application, Integration                                       David T. Krohne                                Copyright © 2015 Oxford University Press

14 Avoidance Adaptations Metabolic Avoidance
Obligate hibernators Facultative hibernators Quickly enter a torpid state Quickly aroused by external stimuli. Drop in the metabolic rate and body temperature not as deep as in the obligate hibernators Must enter hibernation each year Accumulate significant fat reserves Metabolic rate and body temperature drop Heart rate and respiration slow down Kidney function often ceases Ecology: Evolution, Application, Integration                                       David T. Krohne                                Copyright © 2015 Oxford University Press

15 Benefits of Hibernation
Avoidance of harsh conditions Protection against predators Survival of hibernators (orange) is higher than in physically and ecologically similar non-hibernators (blue) What may be the costs of hibernation? Bats Other mammals Ecology: Evolution, Application, Integration                                       David T. Krohne                                Copyright © 2015 Oxford University Press

16 Avoidance Adaptations Behavioral Avoidance
Migration—the seasonal movement from one region to another and back May be obligate or facultative Advantageous when the abiotic challenges are seasonal and predictable External stimuli serve as cues for migration Ecology: Evolution, Application, Integration                                       David T. Krohne                                Copyright © 2015 Oxford University Press

17 Avoidance Adaptations Behavioral Avoidance: Large Scale
Migration—the seasonal movement from one region to another and back May be obligate or facultative Advantageous when the abiotic challenges are seasonal and predictable External stimuli serve as cues for migration Ecology: Evolution, Application, Integration                                       David T. Krohne                                Copyright © 2015 Oxford University Press

18 Benefits and Costs Of Migration
Avoid harsh environmental conditions Expand resource base by separating breeding and overwintering grounds Costs Considerable energy cost High risk of mortality Ecology: Evolution, Application, Integration                                       David T. Krohne                                Copyright © 2015 Oxford University Press

19 Avoidance Adaptations Behavioral Avoidance: Small Scale
Behavioral thermoregulation Moving to spots with more favorable temperatures Basking Modifying posture Contact with the substrate Affects heat exchange by conductance and convection Local stress and predator avoidance Burrowing Nocturnal behavior Ecology: Evolution, Application, Integration                                       David T. Krohne                                Copyright © 2015 Oxford University Press

Download ppt "Adaptations to the Physical Environment"

Similar presentations

$100 Theory Taking the Heat Good Behavior Staying Alive Relation- ships $200 $300 $400 $500 $100 $200 $300 $400 $500 $100 $200 $300 $400 $500 $100 $200.

$100 Theory Taking the Heat Good Behavior Staying Alive Relation- ships $200 $300 $400 $500 $100 $200 $300 $400 $500 $100 $200 $300 $400 $500 $100 $200.
Chapter 4 - Temperature. Question? Along the shoreline of Lake Michigan in Michigan, fruit trees are grown in abundance. These plants are not found 20.

Chapter 4 - Temperature. Question? Along the shoreline of Lake Michigan in Michigan, fruit trees are grown in abundance. These plants are not found 20.
Biology 12.

Biology 12.
Thermoregulation.

Thermoregulation.
1 Chapter 7 Animal adaptations to the Environments.

1 Chapter 7 Animal adaptations to the Environments.
16-1 D. Thermoregulation 1. Animals show two types of responses to changing environmental temperature.

16-1 D. Thermoregulation 1. Animals show two types of responses to changing environmental temperature.
Key Area 4 : Conformers and Regulators

Key Area 4 : Conformers and Regulators
The Ocean’s primary Productivity

The Ocean’s primary Productivity
Chapter 3 IN PEARSON book

Chapter 3 IN PEARSON book
Interactions in an Ecosystem

Interactions in an Ecosystem
Detecting temperature change Chapter 10; p309. Regulating heat exchange Heat exchange – heat transfer between the internal and external environment. Factors.

Detecting temperature change Chapter 10; p309. Regulating heat exchange Heat exchange – heat transfer between the internal and external environment. Factors.
Chapter 40-Coordination and Control

Chapter 40-Coordination and Control
Population Dynamics (4.1)

Population Dynamics (4.1)
VCE Biology Unit 2 Area of Study 01 Adaptations of Organisms Living in extreme terrestrial environments.

VCE Biology Unit 2 Area of Study 01 Adaptations of Organisms Living in extreme terrestrial environments.
1) Acclimation (reversible): short-term change in structure or function (biochemical pathways) shift in range of physiological tolerances of an individual.

1) Acclimation (reversible): short-term change in structure or function (biochemical pathways) shift in range of physiological tolerances of an individual.
U Chapter 40 ~ An Introduction to Animal Structure and Function.

U Chapter 40 ~ An Introduction to Animal Structure and Function.
Key Area 5 : Metabolism in Adverse Conditions

Key Area 5 : Metabolism in Adverse Conditions
Animals. Animals need Air Food Water A suitable place to live.

Animals. Animals need Air Food Water A suitable place to live.
Ch. 40 Warm up 1.Define and give an example of homeostasis. 2.Sequence the organization of living things from cell to biome. 3.Describe negative and positive.

Ch. 40 Warm up 1.Define and give an example of homeostasis. 2.Sequence the organization of living things from cell to biome. 3.Describe negative and positive.
$100 Theory Taking the Heat Getting Out Staying Alive Relation- ships $200 $300 $400 $500 $100 $200 $300 $400 $500 $100 $200 $300 $400 $500 $100 $200.

$100 Theory Taking the Heat Getting Out Staying Alive Relation- ships $200 $300 $400 $500 $100 $200 $300 $400 $500 $100 $200 $300 $400 $500 $100 $200.

Similar presentations

Ads by Google