Mrs. Herman 2015 CHANGES OVER TIME

Evolution is the change over time in a population of related organisms. WHAT IS BIOLOGICAL EVOLUTION?

 All living things have a common ancestor.  There are variations of individuals.  Adaptations – (structural, behavioral, functional).  Organisms produce more offspring than can survive.  Competition exists among individuals.  Natural selection.  Artificial selection (selective breeding). OVERVIEW OF THE THEORY OF EVOLUTION

Adapted from: Ms. Weinberg toad Animal Adaptations

Have you ever wondered how animals are able to survive in the wild? Animals have certain adaptations that help them to survive.

Think about the way you dress in the winter. You don’t wear your shorts and bathing suit when it’s snowing outside! You wear warm clothes, and maybe even a hat and mittens to protect yourself from the weather.

And what if you are having a snowball fight? You probably run away from the person throwing at you, and maybe even try to sneak up on that person and throw some snowballs!

The way you dress in the winter, as well as the way that you run and hide from someone throwing snow at you are kinds of … Adaptations An adaptation is an inherited trait that increases an organism’s change of surviving and reproducing in its environment.

We can separate adaptations into two categories: Physical (structural and functional) AND Behavioral A D A P T A T I O N S

Physical adaptations are body structures that allow an animal to find and consume food, defend itself, and to reproduce its species. Physical adaptations help an animal survive in its environment. Hey! I’m a walking stick. I look just like a stick you’d find on the ground. © A. Weinberg

Physical adaptation Camouflage (use of color in a surrounding) The chameleon can change its color to match its surroundings.

Mimicry (looking or sounding like another living organism) The Viceroy butterfly uses mimicry to look like the Monarch butterfly. Can you tell them apart? Physical adaptation I’m the Monarch! I’m poisonous I’m the Viceroy! I’m not poisonous

Chemical defenses (like venom, ink, sprays) Physical adaptation

Body coverings & parts (claws, beaks, feet, armor plates, skulls, teeth) Physical adaptations The elephant’s trunk is a physical adaptation that helps it to clean itself, eat, drink, and to pick things up.

Now let’s learn about Behavioral Adaptations… Behavioral Adaptations allow animals to respond to life needs.

Each organism has unique methods of adapting to its environment by means of different actions. Behavioral Adaptations are animals’ actions.

We can divide Behavioral Adaptations into two groups: Instinctive Learned These behaviors happen naturally & don’t have to be learned. These behaviors must be taught.

Instinctive behaviors happen naturally & don’t need to be learned = Finding shelter Methods of gathering & storing food Defending oneself Raising young Hibernating Migrating

Learned behaviors Obtained by interacting with the environment and cannot be passed on to the next generation except by teaching. = language Riding a bicycle cooking

NATURAL SELECTION Over time, natural selection results in changes in inherited characteristics of a population. These changes increase a species fitness in its environment

The organisms whose variations best fit them to the environment are the ones who are most likely to survive, reproduce and pass these desired variations on to the next generation. (survival of the fittest) CONCEPTS OF NATURAL SELECTION

Competition exists among individuals for mates, territory and food. CONCEPTS OF NATURAL SELECTION

Organisms produce more offspring than the environment can support because only a small number will survive to adulthood. CONCEPTS OF NATURAL SELECTION

Variations exists among individuals within a species. CONCEPTS OF NATURAL SELECTION

ARTIFICIAL SELECTION (SELECTIVE BREEDING)  Selective breeding - process by which people choose which traits they would like to have in the next generation of offspring.  They then select the organisms, having those traits, to breed in order to produce offspring with those traits. An example of this is breeding “teacup” dogs. Breeders cross small dogs in an attempt to produce offspring that are tiny.

EVIDENCE OF EVOLUTION  The Fossil Record  Geographic Distribution of Living Things  Homologous Body Structures  Similarities in Early Development  Vestigial organs

EVIDENCE OF EVOLUTION  The Fossil Record  Geographic Distribution of Living Things  Homologous Body Structures  Similarities in Early Development  Vestigial organs

EVIDENCE OF EVOLUTION  The Fossil Record  Geographic Distribution of Living Things  Homologous Body Structures - structures that have different mature forms in different organisms, but develop from the same embryonic tissue  Similarities in Early Development  Vestigial organs

EVIDENCE OF EVOLUTION  The Fossil Record  Geographic Distribution of Living Things  Homologous Body Structures  Similarities in Early Development  Vestigial organs

EVIDENCE OF EVOLUTION  The Fossil Record  Geographic Distribution of Living Things  Homologous Body Structures  Similarities in Early Development Vestigial organs - organs that serve no useful function in an organism, i.e. appendix, tail bone. Rib cage of a Python

Changes….. Environments are complex. Species must adapt to an environment’s living parts as well as it’s nonliving parts. Nonliving parts include temperature, water, nutrients in soil and climate. Deciduous trees shed their leaves due to changes in climate. Camouflage, mimicry and mouth shape are adaptations mostly to an environments living parts. Living and nonliving factors are always changing. Even slight environmental changes affect how species adapt. If a species is unable to adapt, it becomes extinct. The fossil record contains many fossils of species that were unable to adapt to change. From text page 222

EVOLUTION OR EXTINCTION Biological Evolution - the change over time in populations of related organisms. Extinction – occurs when the last individual organism of a species dies.