INVESTIGATION 8 “ADAPTATION”

WHY DO CHANGES IN AN ORGANISM AFFECT ITS CHANCES OF SURVIVAL?

Living things have basic needs, such as energy, water, gas exchange, etc… to survive.Every organism has varying needs for

things like water, gas exchange, etc…

WHY DO CHANGES IN AN ORGANISM AFFECT ITS CHANCES OF SURVIVAL?

The resources for life originate in an organism’s environment. Critical relationship between

environment and organism. When an environment changes,

organisms that interact with it are influenced. Improve or decrease organism’s chance for

survival.

WHY DO CHANGES IN AN ORGANISM AFFECT ITS CHANCES OF SURVIVAL?

Changes enhance one organism’s ability to survive and reproduce more offspring while it decreases the chances of another organism.

ADAPTATIONS

Organisms have adaptations that allow them to live an environment.

Every organism has a unique set of adaptations to live in its environment.

Examples: Sea otters live in the sea. Desert tortoises live in the desert.

ADAPTATIONS

Adaptations are:Physical attributes (structures and

functions) ORBehaviors that enhance an organism’s

opportunity to live and reproduce in its environment.

ADAPTATIONS

Organisms have different types of adaptations:Structural Adaptations Functional Adaptations Behavioral Adaptations

ADAPTATIONS

The particular combination of adaptations expressed by an individual defines the lifestyle that that organism will lead and the environment in which it can survive.

VARIATION WITHIN A SPECIES

Organisms of the same kind are all members of the same species.

All members of a species have similar adaptations and, therefore, the ability to live in the same environment. The members of a species that are living

together and interacting constitute a population.

VARIATION

Within a population, there is variation.

Variation is the amount of difference in physiological and/or behavioral attributes exhibited by the members of a population. Example: Walkingsticks color

BIOLOGICAL IMPLICATIONS OF VARIATION

When the environment provides abundant resources, all members of a population share in the bounty and survive. This is the exception.

BIOLOGICAL IMPLICATIONS OF VARIATION

Factors in the environment is in limited supply or pushing the limits of tolerance of the organisms. Variation is essential here!

BIOLOGICAL IMPLICATIONS OF VARIATION

The individuals that have structures or behaviors that allow them to break slightly harder seeds, run a little faster, etc…., will have a survival advantage over the members of the populations when the environment changes.

What examples have we done in class that reinforces this statement? Why?

BIOLOGICAL IMPLICATIONS OF VARIATION

As a result of natural variation in a population, the population may survive failure of a primary food source, invasion by a predator, reduction in solar radiation, or drought.

BIOLOGICAL IMPLICATIONS OF VARIATION

*** Different members of the population will have the advantage depending on what environmental factor imposes pressure on the population.

The results is that some members will survive to reproduce ensuring the survival of the species and the continuing of the population.

FEATURES AND TRAITS

Organisms have distinctive features that make them recognizable.

Examples: Snakes have scales, color patterns, eyes, and mouths.

Ducks have feathers, beaks, webbed feet, and eyes.

FEATURES AND TRAITS

Features: are structures of organisms.

FEATURES AND TRAITS

There is tremendous variation in features from species to species, but all individuals of the same species have the same features…

HOWEVER… there can be variation in how the features look within a species.

FEATURES AND TRAITS

The appearance of a feature within a species is called a trait. A trait is the particular manner in which an

organism exhibits a feature, that is, how it looks.

Example:Black bears have all the same features:

four legs, short tail, small ears, two eyes, long, course fur, and a brown nose, etc… The color of the fur can vary. The fur color is the feature and the color of the

fur (brown, black…) is the variation.

FEATURES AND TRAITS

Case Study: Peppered Moth StudyA classic investigation looked at the feature

of wing color in the peppered moth of England.

The moth’s wing color can vary from almost white with dark dots to completely black.

FEATURES AND TRAITS

A Case Study: Peppered MothsWhen the Industrial Revolution filled the air

with pollutants, the light-colored moths died and the dark-colored moths survived. Why?