ANIMAL BEHAVIOR A BIOLOGICAL PERSPECTIVE SECTION 1 THE SIENTIFIC STUDY OF ANIMAL BEHAVIOR The relationship between Bats and Moths o Lazzaro Spallanzani reasoned that bats must have a super keen sense or senses o He hypothesized that they is highly sensitive smell hearing or vision o Respectable application of the scientific method o Donald Griffin proved that bats produce ultrasound while flying in the dark Bats fly screaming yelps of ultrasound while listening in the dark for the echo The bat aligns itself with the position of the echo source and capture moths Ultrasound sound frequencies below the range of human hearing Sonar Echolocating recognition of objects by their sound echo o The moths have ears that hear well specifically at ultrasonic frequencies Evasion avoiding capture of contact The relationship between male and female guppies o Male guppies are smaller than females and have brightly colored fins o Male is attracted to the stimulus of a female bulging with ovaries full of unfertilized eggs o He gets in her face and contorts his body into an S shape while flaring his fins Display communicating signal given by an animal usually a special movement body posture or color pattern o In a guppy tank with 1 male and 1 female each male displayed about once every 5 minutes Steps of the scientific method Observe question hypothesize predict experiment 1 An unexplained phenomenon is observed and described 2 All plausible falsifiable hypothesis disprovable explanations are put forth Your hypothetical predictions are used to design an experiment 3 Hypotheses are tested based on their predictions 4 A falsified hypothesis is rejected as incorrect 5 An un falsified supported hypothesis is inferred to be correct for the particular conditions of the study Infer conclude by reasoning 6 A hypothesis with broad application to predicting natural processes and has results replicated by independent techniques or that is supported by several lines of evidence is a rule or theory Prove demonstrate to be completely true Main approaches to studying animal behavior and their attributes and limitation o Field observation an approach to studying behavior in which the scientist observer studies the animal in its natural environment and does not interfere with its behavior Attributes Weakness The documentation of natural events and the range of normal responses to them in the milieu in which the species actually lives the inability to ascertain what features of the many stimuli present might have caused a response Also some important behaviors rarely occur and cannot be repeatedly witnessed o Field manipulation an approach in which the scientists manipulates some feature stimulus or condition hypothesized to be influencing the animal s behavior Attributes Replication to be sure that the animal s response wasn t just chance As with field observations the actions occur in a natural condition providing some assurance that the action is not caused by strange surroundings the behavior The uncertainty that some unforeseen unmeasured stimuli actually influenced Weakness o Controlled laboratory experiment an approach in which the environment of the animal is controlled by the scientist experimenter especially the stimulus hypothesized to influence the behavior in question o Attributes Establishes cause and effect replication and give you precise conditions o Weakness The behavior of wild animals in the small sterile enclosure is often unnatural and very different from how they act in the normal environment so it s not useful for inferring about ecological aspects of behavior SECTION 2 THE PERCEPTUAL WORLDS OF ANIMALS Animals uses their abilities to detect stimuli ranging from light waves to unique chemicals to survive and reproduce in a very complex dynamic and risk filled environment Stimuli physical properties of the environment that excite sensory receptors Perceptual world the collective stimulus sensitivities of an animal Certain physical properties stimuli of the surrounding environment can inform an animal about the state of important conditions that affect the individual s survival o Classes of informative Stimuli Radio magnetic waves light bees see UV light and color when looking to pollenate flowers snakes detect infrared waves to get their food Sound bats and moths important in the ocean Chemicals Gravity Touch Electricity Magnetism How the Milieu Shapes Senses o Even when different species use the same class of stimuli they often differ in their sensitivity to it they have different thresholds Threshold lowest measured level of stimulation that excites a response o Sense capacity to respond to various classes of stimuli o The environment of an animal shapes their senses to fit them uniquely for them o Sign stimulus unique qualities to a species that triggers a functional response o Pheromones moth sex perfume Female moth perches on a branch and exudes a chemical which isn t detected by bats or even the males of other moth species Males flies upwind to find and court the female o Electric fish o Rattlesnakes o Sharks Find prey and mates by sensing disturbances to the mild electric field Tissue produce the field which can signal other members of the species Rattlesnakes have specialized heat sensitive receptors As a rat approaches its body heat is sensed by the snake s pit organ Have highly sensitive electroreceptors that detect weak electrical discharge The bug Detector Brain program o Hypothesis a frog needs to test out and learn each kind of edible bud or the frog brain is pre programmed for all edible insects o Tested in controlled lab experiment on from with electrodes placed to record the level of activity in the part of their brain that triggers prey capture behavior o The result was that only small dark moving rounded shapes elicited consistent neural excitement and pre strike behavior In general while features of sing stimuli differ among species higher animals all have the equivalent of big detectors o Bug detector nervous system program in the brain of frogs that interprets any small dark moving object as a target and triggers tongue flick SECTION 3 BEHAVIORAL ADAPTIONS Think of animal behavior from 2 perspectives o Cause o Consequence provides insight into their origins and underscores the centrality of genes Niko Tinbergen studied seagulls and their removal of broken eggshells o Parent gull picks up shards of broken shell and flies off to drop them far from the colony o Sharp
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