Animal Behavior: Innate

Presented by :

ShushmaKumari

HOD & Assistant Professor,

Zoology, J. D. W. College, Patna

B.Sc. Part-I Paper - II

The first type is innate behavior.From Latin . innatus "inborn,“

Innate behaviors are those you develop on your own,

which do not need to be taught or learned.

Innate behavior is something the animal is born knowing

how to do.

Examples include fish swimming and geese migrating.

What other examples can you think of?

Innate behavior

Behavior determined by the "hard-wiring" of the nervous

system is Innate behavior .

It is usually inflexible, a given stimulus triggering a given

response.

Example: A salamander raised away from water until long

after its siblings begin swimming successfully will swim

every bit as well as they the very first time it is placed in the

water.

Clearly this rather elaborate response is "built in" in the

species and not something that must be acquired by practice.

Types of innate behaviorIrritability

Tropism

Nasties

Taxis

Kinesis

Reflex action

Instinct

Motivation

Let‘s study detail

Types if innate behavior1: Irritability

def.: Irritability is an excessive response to stimuli.

Conditions

Irritability can occur in people experiencing any of a variety

of conditions, including:

Anxiety

Alcoholism

Fever

2: tropism :

Cause of name: (from Greek trope, "a turning")

Def: it is a biological phenomenon, indicating growth or turning

movement of a biological organism, usually a plant, in response to an

environmental In tropisms, this response is dependent on the

direction of the stimulus

Tropisms are typically associated with plants.

Types of tropism

Chemotropism, movement or growth in response to

chemicals

Geotropism (or gravitropism), movement or growth in

response to gravity

Heliotropism, movement or growth in response to sunlight

Sonotropism, movement or growth in response to sound.

Hydrotropism, movement or growth in response to water

Phototropism, movement or growth in response to lights or

colors of light (e.g.- the sunflower)

Types of tropismThermotropism, movement or growth in response to

temperature

Electrotropism, movement or growth in response to an

electric field

Thigmotropism, movement or growth in response to touch

or contact

3:nastiesDef:

these Are non directional responses to stimuli (e.g.

temperature, humidity, light irradiance), and are usually

associated with plants

The movement can be due to changes in turgor or changes in

growth.

Nastic movements differ from tropic movements in that the

direction of tropic responses depends on the direction of the

stimulus, whereas the direction of nastic movements is

independent of the stimulus' position.

Types of nastiesEpinasty: downward-bending from growth at the top, for

example, the bending down of a heavy flower.

Photonasty: response to light

Nyctinasty: movements at night or in the dark

Chemonasty: response to chemicals or nutrients

Hydronasty: response to water

Thermonasty: response to temperature

Geonasty/gravinasty: response to gravity

Thigmonasty/seismonasty/haptonasty: response to contact

Examples of nasties

To be contd…