Animal Behavior

1. Animal Behavior Perspectives of Behavior

2. Ethology Sponge #1 • Behaviors always have a cause usually caused by a stimulus. • Proximate Causes of behavior are those stimuli that directly cause a behavior. • Ultimate Causes of behavior are those causes that help in the “ultimate” survival of a species. • Explain each of the following human behaviors in terms of their proximate AND ultimate causes: • Walking and Running • Eating • Arguing with a friend • Flirting with a boy or girl • Getting nervous before a big event-a game or interview

3. Ethology • Ethology is the the study of the behavior of animals and the proximate and ultimate causes to those behaviors • Ethological studies require comparisons between a variety of species whose morphology, behavior, and ecology are diverse. • All behaviors reflect the range of solutions which have evolved to meet the needs of the organism in their given environment.

4. Terms in Review • Some basic Biological terms in review from this type of study include: - Morphology - refers to the study of the similarities in structure and function of living organisms (example: the hand and the fin and the wing) - Ecology - refers to the study of the interaction between a living organism(s) and the environment. - Behavior - is defined as an objective and mechanistic description of acts without reference to function. - Stimulus - anything that causes an animal to respond - Response - an action caused by a stimulus

5. Ethology, Morphology and Taxonomy • Since ethology is a comparative study of behaviors it’s important to know how we compare • Morphology is the study of the similarities and differences in living things (in this case how animals behave) • A part of morphology is being able to relate animals to each other using classification • Taxonomy is the study of morphological similarities and differences and their relatedness (classification)

6. Activity - Taxonomy & Morphology • Cladistics is a type of classification scheme used in taxonomy • Similarities (synapomorphy) & differences (pleisiomorphy) are used to create a type of family tree • Pick any three animals that you know about and create a Cladogram of their behaviors diagraming synapomorphies and pleisiomorphies for each

7. Basic Needs & Behavior • All behavior satisfies one of the basic needs of all living things. • Finding food • Not becoming food • Sexual reproduction • Each behavior has a cost-benefit (what it gets versus what it costs) component to it. • Consider the three basic needs for animals. Pick any two animals and discuss the cost benefit for each in nature

8. Proximate Causes • Proximate causes are immediate causes for a behavior • Proximate causes refer to those "closest" to the behavior • Proximate Causes have three components of activation for animals: Input, Integration and Output • Animals are not like computers (input  output) • Input is usually a stimulus, integration is how the animal internally processes the stimulus and output is the response to the stimulus

9. Ultimate Causes • Ultimate Causes are autonomic responses in organisms • Autonomic = automatic (you respond quickly and without hesitation, thought or consideration) • Ultimate causes are evolutionary processes that are successfully reproduced in organisms over time • Adaptation is a process by which groups of organisms maintain change what they do and/or how they do it or die • Evolutionary processes are caused by mutations, which provide variation, and selection, which determines the variations that are preserved and perpetuated • Behavior is subject to evolution. • Behavioral changes (for example, the development of a new food preference or mode of foraging) can be a first step of evolutionary adaptation, followed by the natural selection of appropriate changes in body form and other characteristics

10. Controls to Behavior • Controlled by interactions between the environment and lineage • The environmental interaction refers to the successful expression and reproduction of a trait over time • Lineage refers to the heritable information gained from parents, grandparents (ancestors) that make each organism unique

11. Environmental Interactions • As organisms interact with biotic and abiotic factors in the environment behavior is produced • Biotic factors = other living things • Abiotic factors = non living things • Behaviors produced are either good or bad for the organism • Some behaviors may get an organism killed and some may help the organism survive in the environment and further respond to biotic and abiotic factors in the environment • Successfully passing on behaviors through reproduction = evolution

12. Perspectives of Behavior • Perspectives are ways of studying behavior • Each perspective has a specific field of biology as its target • Each perspective asks different questions and have different methods of answering them • Each perspective is appropriate to the level of organization that is being studied, but they are all studying behavior and the consequences of behaviors • Prospective Fields: • Developmental Perspective • Ecological Perspective • Evolutionary Perspective • Physiological Perspective

13. Physiological Perspective • The biological needs of the organism through it’s expression of a behavior that affect it’s internal chemistry and thus it’s outward expression. • NEUROBIOLOGY involves the nerves and their activities, how they are linked together to transmit information through the organism for specific purposes. For convenience we sometimes distinguish INPUT, INTEGRATION, and OUTPUT . • INPUT involves the senses -- the only way we can get information about the always changing environments in which we must function; • INTEGRATION involves how the the brain regulates motivation, affect, and cognition to cause behavior (various bits of information are encoded in the nervous system and interact with each other to affect behavior) • Within the integration component we will distinguish three systems that overlap significantly but are in general responsible for fundamental aspects of behavior: MOTIVATION, AFFECT, and COGNITION. • OUTPUT involves the actions of the nervous system on "effector" organs that accomplish its goals such as endocrine glands and muscles

14. Developmental Perspective • Study of the behavioral development over it’s lifetime • Changes in individuals - becoming "all you can be” - involves the progressive expression of genetic potential • ONTOGENY has to do with the sequential expression or unfolding of the genetic potential in a protected environment such as the womb or an egg. • EXPERIENCE has to do with expression of genetic potential in the environment an animal finds itself, such as after birth • changes in behavior occur as a result of experience is learned either through non-associative or associative processes • EPIGENESIS it the term used for the unfolding of genetic potential as a function of its interaction with the environment • Specific experiences are more-or-less potent in activating specific genes or facilitating specific parts of the path from gene activation to the eventual expression of a trait.

15. Ecological Perspective • The contexts in which individuals function-climate, geology, and other animals • involves the context in which behavior occurs and the organism's interactions with the environment • ENVIRONMENT involves the ecosystem and all its time or spatial dimensions: • climatic variables such as moisture and temperature, other organisms --predators, prey, companions, mates, etc. • Environmental thinking sometimes helps us understand the organism's inner environment --blood chemistry, endocrine tone, hunger, experience of various physiological needs. Rhythms, cycles, present and past environmental fluctuations

16. Evolutionary Perspective • A perspective is a way of looking at a behavior. • The evolutionary perspective considers both the ultimate cause and the evolution of a species due to those ultimate causes. • Remember that evolution is the study of change across generations and the "ultimate cause" of behavior. • Involves biological variations that affect changes in traits. • Comparative behavior pattern seen in relatives over time that aid in the survival of the species over generations • Since behavior is controlled by genetics it is important to know the following: • GENES - biological units of inheritance • MEMES - cultural units of inheritance • FITNESS - number of successful offspring, capacity to project "biologically relevant information" (such as genes or memes) into the next generation

17. Natural Selection & Darwinian Theory • Charles Darwin was a naturalist that suggested biologically relevant information is transmitted from generations on he said the following: • Variation within a species - Variation exists between individuals in a species • Heritability - Organisms produce more offspring than environment can support • Adaptation - Competition exists between individuals and those individuals that adapt will survive • Natural Selection - biotic and abiotic factors will affect individuals allowing them to reproduce successfully or not • Organisms whose variation best fit them to the environment are the most likely survive, reproduce and pass those desirable variations to the next generation

18. Selection Modes • Selection is defined as a relationship between fitness and phenotype • Fitness is defined using terms of three kinds of SELECTION MODES: • directional selection in which a trait is linearly related to fitness, • Stabilizing or convergent evolution is when there is an optimal value for the trait of interest, and • disruptive or divergent evolution is when there are individuals with the smallest and largest values of the trait have the highest fitness and individuals with intermediate traits are at a fitness disadvantage.

19. Selection Modes

20. Selection Modes • Directional Selection - favors individuals possessing extreme values of a trait (like long necks in giraffes, coloration in peppered moths), which causes the population to move in a particular direction. • Example: If a climate becomes colder, a population may evolve in a consistent direction in response - thicker fur

21. Selection Modes • Stabilizing Selection - acts against individuals who deviate too far from the average, favors the average. • Example: sizes in lizards: large lizards may be subject to predation, small lizards have a hard time defending territories, natural selection favors the average

22. Selection Modes • Disruptive Selection - adapts individuals in a population to different habitats. Its similar to directional selection, but it favors either extreme, not just one extreme. Disruptive selection may occur in an area that provides different resources. • Example: Galapagos finches had a variety of food choices, smaller birds fed on small seeds, larger birds fed on large seeds, natural selection favors both the large and the small bird, but not the average bird (who would compete for both resources)

23. Sexual Selection • Charles Darwin distinguished sexual selection as a variance in the number of mates. • Sexual selection acts to refine characters in the phenotypes between males and females types. • The action of sexual selection can take the same three modes that are discussed on the previous slide for natural selection. • Directional, stabilizing or disruptive selection.

24. Smoke-Detector Principle • Some evolutionary processes produce traits that appear as false responses or behaviors • Smoke-Detector Principle - behavioral response an organism produces false response to a stimulus • The intent - produce same response every time hoping that once the “real” situation comes, the respond does not cost your life • The cost of responding to 100 false alarms is better than the cost of losing life • Human emotion is an example • Explain how the following two human emotions can serve as a “smoke detector principle” for humans? • An infant that cries when they get hungry • You get scared, someone startles you and you scream and jump

25. Principles of Evolutionary Thinking Thoughts on disease, evolution and behavior • Modern epidemics are most likely to arise from the mismatch between PHYSIOLOGICAL DESIGN of our bodies and NOVEL ASPECTS of our environment • Our DESIRES, shaped in the ancestral environment to lead us to actions that tended to maximize reproductive success, now often lead us to disease and early death • Some GENES that cause disease may also have benefits, and others are quirks that cause disease only when they interact with novel environmental factors

26. Principles of Evolutionary Thinking • GENETIC SELF-INTEREST will drive an individual's actions, even at the expense of the health and longevity of the individual created by those genes • SYMPTOMS of infection can benefit the pathogen, the host, both or neither • Disease is INEVITABLE because of the way that organisms are shaped by evolution • Each disease needs a PROXIMATE EXPLANATION of why some people get it and others don't, as well as an EVOLUTIONARY EXPLANATION of why members of the species are vulnerable to it • Diseases are not products of natural selection, but most of the VULNERABILITIES that lead to disease are shaped by the process of natural selection

27. Controls to Behavior II • Remember that behavior is controlled by two things • Environment and genetics (heritable traits) • Natural Selection from the level suggests the following: • Variation - Members of a species may differ in their characteristics. Alternate alleles for characteristics exist in nature (tall versus short). • Heredity - Alleles for a characteristic can be transmitted from parent to offspring by sexual reproduction. • Differential Reproduction - Some alleles are better at causing bearers to transmit copies of those alleles to offspring better than others.

28. Heritable Traits • DNA = Deoxyribonucleic acid • The genetic code (genotype) for all living things transcribed through development into the physical being (phenotype) we call an animal • DNA inherited from parents (the survival of a trait transmitted) • Essentially if you reproduce before you die, you transmitted your traits on to your child (=offspring) • DNA make up chromosomes that are transmitted during sexual reproduction

29. Genes Control Behavior • A gene is a segment of DNA (an allele) that controls the phenotype of an animal • A phenotype is a behavior in this case • Animals have 20 or more chromosomes and each chromosome contains more than 100 genes. • Each gene controls a different phenotype • Genes interact in complex ways to make complex organisms with complex behaviors

30. Basic Genetics • Every animal inherits chromosomes from each parent • Half of your chromosomes come from each parent to make you the whole individual • Animals are therefore hybrids (a cross between their mother and their father) • The assortment of the traits that animals get from each parent make each animal unique genetically (genotypically) and physically (phenotypically)

31. Genes and Populations • Mutations - Random changes in genetic sequence causes changes in phenotype • Gene Flow - Mutations can dominate in a population because of environmental variables thus pushing more individuals in the population through reproductive fitness levels to express a specific trait. • Genetic Drift - Movement of traits into a population thus focusing the gene pool of the population into one direction • Non-Random Mating - Mating preferences and selection of mates predisposes populations to express some traits over others.