Evolution Evolution The process of change over time

Evolution

Evolution: The process of change over time. • There are natural variations in all populations. • As climate changes occur, and as pressures in terms of food, space, shelter and predation occur, some variations allow a species to survive. • The members who survive, reproduce causing the change to become a characteristic of the species.

Speciation: Separation into new species. • Geographic isolation cause two different natural variations to become prominent causing 2 separate species. • Reproductive isolation can have the same effect.

What is extinction and what causes it? • A population is extinct when the last of that species is dead. • Example: There are no more dinosaurs. • What happened? Their habitat was destroyed. When they no longer have what they need to live, they die.

Fossils • These are imprints or remains of living things. • In undisturbed layers of sedimentary rock, the deeper it is, the older it is. • Give us information about extinct species.

Homologous vs. Analogous Structures • Homologous means they • Analogous means they have the same function but come have the same origin, but from different origins. may be different now. • Example, the upper arm • Example, bird wings and wings of bats. bones in dogs, cows, cats and monkeys.

Homologous Structures

Vestigial Structures • Structures that are reduced in size they are no longer functioning

Embryology • All vertebrates start off very similar in their development.

Taxonomy

Classifying Organisms • Taxonomy – the science of classifying and grouping organisms. • Binomial Nomenclature – naming organisms using a two-part name. – First word is the Genus (always capitalized) – Second word is the Species (lower case)

Classifications • Kingdom Largest • Phylum • Class • Order • Family • Genus • Species Smallest • • King Phillip Came Over From Greece Sneezing

6 Kingdoms • • • Eubacteria Archaebacteria Protista Fungi Plantae Animalia Prokaryotes Eukaryotes

Eubacteria & Archaebacteria • • • Includes all prokaryotes Most are unicellular Microscopic Eubacteria are found everywhere Archaebacteria live without oxygen; found in extreme habitats (salt lakes, swamps)

• Bacteria are classified based on their shape – Spherical – Rod-shaped – Spiral

Kingdom Protista • Eukaryotic • Unicellular & Multicellular • Most diverse group of all the kingdoms • Found mainly in moist environments • Ex: amoebas

Kingdom Fungi • • Eukaryotic Unicellular & Multicellular Many are decomposers Ex: mushrooms

Kingdom Plantae • • • Multicelluar Eukaryotes Perform Photosynthesis Autotrophs or Producers Stationary (cannot move around) Have cell walls

Kingdom Animalia • Multicellular Eukaryotes • Consumers or Heterotrophs • Mobile – can move from place to place • No cell walls • Have tissues that are organized into organs and organ systems

Learning Check #1 Which is the largest classification of organisms? A. Species B. Genus C. Family D. Order D #2 How are bacteria classified? According to their shape

49 Which of these classifications is most specific? A Family B Genus C Phylum D Order Answer: B

8 Some bacteria benefit mammals by • Kingdom Bacteria has helping with — beneficial and harmful F growth members G defense H digestion J respiration • The best answer here is H, since digestion systems of mammals contain bacteria. • Bacteria found in the respiratory system usually result in illness, which would trigger the defenses, not help them.

The bacteria Bacillus thuringiensis produce protein crystals that are toxic to the digestive system of insects. How can these bacteria be used to control insects in crops? F G H J Apply the bacteria to growing plants. Expose the bacteria to low levels of light. Remove plants from areas containing the bacteria Treat the bacteria with a solution of the protein crystals Answer: F

12 The bullfrog, Rana catesbeiana, is most closely related to the — F spotted chorus frog, Pseudacris clarki G Asian flying frog, Polypedates leucomystax H northern leopard frog, Rana pipiens J African bullfrog, Pyxicephalus adspersus

Related in biological terms means family, genus, species. F spotted chorus frog, Pseudacris clarki G Asian flying frog, Polypedates leucomystax H northern leopard frog, Rana pipiens J African bullfrog, Pyxicephalus adspersus • Genus is always a capital letter, species is lower case. • Most closely related would be in the same genus, Rana. • ANSWER? • H

C TAK Obj. 02 TEKS B. 8 C