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• Cellular Organization.
• All organisms consist of one or more cells with highly ordered structures.

• Cells.
• Energy utilization - sun or chemical energy.
• Information - genetic information encoded in genes.
• Growth and reproduction - all organisms grow and reproduce.
• Evolutionary adaptation - gradual, heritable change.

"All living things are made of a cell or cells".

A system of ideas for explaining a general phenomenon.

• Darwin, Wallace, and Evolution
• Until the mid 1800s, most people thought that species do not change over time.
• The work of Charles Darwin and Alfred Russell Wallace provided new insight into changes in species over time (evolution) and lineages of life forms.

• Characteristics of similar species vary from place to place (variation: change with time? Evolution?).
• Geographical patterns suggested lineages gradually change as species migrate.
• Animals and plants on relatively young islands closely resembled those on nearby South American coast.

• Thomas Malthus's Essay on the Principle of
• Population (1798) was one component in
• Darwin's thinking
• Populations can grow faster than resources can keep up
• Even though every organism has the potential to produce more offspring than can survive, population sizes remain relatively constant over time, because RESOURCES ARE LIMITING
• Competition plays a role in determining who survives "lean times"

• Individuals that possess certain characteristics are more likely to survive than those that do not possess those characteristics (through competition for limited resources)
• The ability of an individual to produce offspring is called fitness
• Over time, a trait that increases fitness (adaptation) will increase in a population

• Plant and animal breeders selected certain varieties to produce certain characteristics (artificial selection):
• Character differences (dogs, chickens, Brassica, etc.) appear greater than those in wild populations--great capacity for variability
• Natural variation (change::evolution) occurring in natural populations as well:
• Selective pressure (natural selection) leads to stable change

• Timeline:
• _Original draft of The Origin of Species was written in 1842 but unpublished
• _Alfred Wallace: sent manuscript with similar ideas to Darwin in 1858
• _The Origin of Species published in November 1859

• 1. Heritable trait variation within a population
• 2. Survival and reproduction of individuals with specific traits (leading to increase in frequency of that trait)

• Fossil record
• _Various fossils dating back 3.5 billion years illustrate ancestral and transitional forms of life
• Mechanisms of heredity
• _Genetics accounts for new variations through molecular mechanism

vertebrate Limbs

• Comparative anatomy
• _Homologous structures - same evolutionary origin, but now differ in structure and function
• _Analogous structures - have similar structure and function, but different evolutionary origins (insect wings, bird wings)

• Molecular mechanisms are conserved
• _Biochemistry, DNA analysis
• Development patterns
• _Similarities exist in the development stages of many different organisms

• Evolution:
• _species change over time
• _based on observations of species differences correlated with different geographical locations
• Natural selection:
• _how the species change over time
• _competition for limited resources
• _individuals with traits that favor survival and reproduction contribute those traits to the next generations
• _based on observations of animal breeding
• (artificial selection leads to variation, why not natural selection doing the
• same?)
• _the environment (weather, sun, meteors, other organisms, etc.) plays a major role in defining the traits that permit survival and reproduction

• Fossils illustrate species change.
• Genetics (and molecular biology) illustrate:
• _the determinants of traits (genes).
• _the nature of the gene (DNA).
• _the nature of changes in traits (mutations in DNA).
• _the inheritance of traits (DNA replication and DNA segregation).
• Comparative anatomy:
• _bone arrangement in forelimbs is conserved in higher vertebrates
• Molecular biology and genomics:
• _many genes are highly conserved in evolutionarily distant organisms
• Developmental pathways are similar in different organisms

• Carolus Linnaeus (Karl von Linné): inventor of binomial nomenclature
• Genus: capitalized
• species: lower case
• Both italicized
• Saccharomyces cerevisiae = "sugar + fungus" "beer"; aka, brewer's yeast
• Each scientific name is unique

• What patterns are meaningful representations of
• ancestral lineage? Similarities, differences?
• 1) Does it move or not? (Linnaeus: 2 kingdoms: animals, plants)
• 2) Nucleus or not? (eukaryotes, prokaryotes). Modified Linnaeus scheme, 5 kingdoms: Animals, Fungi, Plants, Protists, Monera
• 3) Similarity of molecular sequence? Carl Woese's phylogenetic tree. Three domains: Bacteria, Archaea, Eukarya

Science: Knowledge of facts, phenomena, and laws, gained and verified by ordered thinking, exact observation, and organized experiment.

• Observation
• Hypothesis - suggested explanation that accounts for observations
• Prediction - something that ought to be true if hypothesis is correct
• Experiment - test of prediction
• Control - checks for factors (other than the one being tested) that might influence experimental outcome

• Cell theory
• All living organisms are made of cells, and all living cells come from other living cells
• Evolutionary change
• Life-forms have evolved varying characteristics to adapt to varied environments
• Evolutionary conservation
• Some characteristics of earlier organisms are preserved and passed on to future generations
• Molecular basis of inheritance
• DNA encodes genes which define and help to control living organisms