Ch. 3 Adapting to the Environment Ch. 4 Population Changes

Species  a group of organisms with similar characteristics that can reproduce among themselves Group of individuals of the same species living in the same place make up a Population

Why do animals look different in different environments? Arctic Fox Desert Fox

Kangaroo Rat Lab Rat Lives in dry climates Feeds on seeds Access to very little water Lives in controlled environment Feeds on Rat Chow Unlimited access to water Hypothesis: Why do we observe these variations in rat species in different environments? Prediction: What adaptations do these animals have?

Reproduction For a species to survive, some members of a species must reproduce 2 Methods of Reproduction: Asexual Reproduction Sexual Reproduction

Asexual Reproduction Single parent has offspring that are genetically identical to parent Advantage – 1. Requires No Mate 2. Lots offspring in a short amount of time Disadvantage – All look same

Asexual Reproduction Number one form reproduction on planet (Bacteria) Examples : a. Budding (Hydra) b. Fragmentation (Sea Star) c. Binary Fission (Bacteria)

Sexual Reproduction Offspring are formed when genetic information from more than one parent combines Advantage – Greater Variation Animals: 2 Parents Female – Egg Male – Sperm Fertilization  joining of egg and sperm

Types of Fertilization 1. External – parents have no contact -- Need Water (Fish, Frogs) 2. Internal – parents have contact -- Mammals, Birds, Reptiles

Genetic information is found on Genes Genes are located on Chromosomes (made of Protein and DNA) Offspring (children) Variation  is an advantage / disadvantage of sexual reproduction and occurs in both plants and animals -- this will help an organism survive or go extinct

Plant Reproduction Like animals, plants can reproduce either asexually or sexually. Some plants can even use both methods. The way a type of plant reproduces is dependent on the plant’s environment.

Plant Reproduction NonVascular Plants (Asexual) Involves Spores (carried Wind/Water/ Animal) Produced Large Numbers Advantage – The greater number of spores (cell) or sporophyte produced, the greater chance they grow into gametophyte (sperm or egg) Examples – Mosses, Liverworts, Hornworts

Plant Reproduction Vascular Plants (Sexual) Pollination  wind transfers pollen from the male cone to the female cone 2 Types 1. Gymnosperms -- no flowers or fruit 2. Angiosperms -- has flowers or fruit

Animal Behavior Animals run from enemies, search for food, battle for territory, and build homes. All of these activities are known as Behavior. 2 Kinds of Behavior :

Innate Behavior (present at birth or show up months / years later) An inherited behavior (genes) that does not depend on the environment. (present at birth or show up months / years later) Examples : Puppies – Chew, Bees – Fly, Whales – Swim, Humans – Walk

Learned Behavior Behavior that has been learned from experience or from observing other animals Example: Language (we have the ability, we do not know the meanings)

Survival Behaviors Find Food a. Predator (eat other animals) b. Prey (animals being eaten) Marking Territory -- area occupied by one animal or group of animals that do not allow other members of the species to enter (Mating, Raising Young, Find Food)

Survival Behaviors Defensive Action – allows animals to protect resources from other animals (skunk, squid, jellyfish) 4. Courtship – need to find mate to reproduce (dance, build nest, fight) Parenting – some offspring need help for survival, while others do not (caterpillar, birds, human)

Seasonal Behavior Migration – animals travel warm environment (food, water, reproduction) Slow Down – save energy a. Hibernation – Winter (Bear) b. Estivation – Summer (Desert animals) 3. Biological Clock – animals keep track of time so they know when to store food, or migrate (length day or temp.)

Evolution the changes in inherited characteristics of a species over time. --As the environment changes, so does the organisms that live in the environment

Mutation Natural Selection (Survival of Fittest) Gene Flow (individuals migrate from place to place) Genetic Drift (individuals leave and are isolated)

Theories How Species Change Over Time

Galapagos Islands (Finches and Tortoises) Charles Darwin December 27, 1831 HMS Beagle Naturalist Galapagos Islands (Finches and Tortoises)

Bird Beak Adaptations:

Theory Suggested that random variations takes place in living things and some external agent in the environment selects those individuals better able to survive.

Book “The Origin of Species” Members of a large population compete for living space, food, and other resources. Those that are able to survive will reproduce and pass their traits to the next generation.

Known as Natural Selection (Survival of Fittest) Darwin’s theory of Evolution is accepted by most scientists today. Known as Natural Selection (Survival of Fittest)

Natural Selection Organisms must be able to: Find Food / Water Have Shelter Reproduce -- > If an organisms is missing one of the three characteristics the organism will go Extinct

4 Parts of Natural Selection Overproduction Genetic Variation with a Population Struggle to Survive Successful Reproduction Examples: Rabbit, Tarantula

Variation  inherited traits that make an organism different from other members of its species. Example– Peppered Moth (England)

Adaptation Variation or characteristic that improves an organisms ability to survive and reproduce in an environment The variation that result in an adaptation can involve an organisms:

Color Shape Behavior Chemical Make-Up Camouflage (blending environment) Mimicry (falsely resemble other species)

Adaptations to Interactions with other Organisms Species adapt to interact with one another in order to survive Example : Honeycreeper (Bird) Lobelia (Flower)

Changes in Genetic Variation Genetic Bottleneck – if a population is decreased rapidly, many characteristics may be lost entirely from a population because all of the individuals with those characteristics dies Example: Florida Panther

Figure 23.5 The bottleneck effect: an analogy

Geographic Isolation  sometimes mountains, lakes, or other geologic features isolate a small number of individuals from the rest of a population.

Ideas about Breeding Plants and Animals have been breed for years to pass on desired traits Selective Breeding – human practice of breeding Animals / Plants that have certain traits Example: More than 150 species Dogs

Speed of Evolution (2 Kinds)

Gradualism Darwin’s Theory------ use Fossil Record Describes evolution as a slow, ongoing process. Darwin’s Theory------ use Fossil Record

Punctuated Equilibrium Gene mutation can result in a new species in a short amount of time. Can be seen today (Bacteria).

Fossils Found in Sedimentary Rock show evidence that living things evolved. Paleontologist  a scientist who studies fossils.

Two Methods To Determine Fossil Age

Relative Dating  look at fossil location in a particular layer of rock; older rock layers are under newer rock layers.

Radiometric Dating  compare the amount of radioactive element with the amount of nonradioactive element in a rock.

The Fossil Records have gaps because most organisms do not become fossils.

More Clues About Evolution

Direct Evidence Such as the development of Antibiotic Resistance in bacteria, supports evolution. Insecticide Resistance – insects immune to pesticides Example – European Corn Borer

Homologous Structure body parts that are similar in origin and structure. Examples--- Human Arm, Bat, Whale

Examples---(Human-Appendix) Vestigial Structure structure that don’t seem to have a function but might have once functioned in an ancestor. Examples---(Human-Appendix)

DNA Best way to see how close organisms are related.