Below Species Ranks• subspecies - a population of several biotypes forming a

more or less distinct regional group of a species - primarily a geographical race or ecotype

• variety - a population of one or several biotypes, forming more or less distinct local groups of a species - primarily local race, or ecotype of very small habitat - many people feel this term shouldn't be used as it is too uncertain what it means

• form - a population of one or several biotypes occurring sporadically in a species population in one or several distinct characters - a genetic variant mixed in with other distinct genetic variants - may be variation in flower color or secondary chemical compounds

• cultivar - a form or race of a plant found only under cultivation

Pitcher Plant - Sarracenia rubra subsp. gulfensis

Pitcher Plant - Sarracenia rubra subsp. wherryi

Acer rubrum – Red Maple - Aceraceae

Acer rubrum var. rubrum

Acer rubrumvar. trilobum

Rosaceae

PeachPrunus persicavar. persica

NectarinePrunus persicavar. nectarina

Violaceae

Two forms of Viola palustris – blue-runner violet

Solonaceae

Several cultivars of the tomato – Lycopersicon esculentum

Geology of Illinois

Garden of the Gods – Shawnee Hills

Apple River, Near Galena

Mississippi Palisades, Savannah, IL

Rockford, Illinois

Starved Rock State Park

Major cycles of variation in temperature

Causes of 100,000 year cycle in temperature variation

EarthduringWisconsinianglaciation

Exposed glacial till

Glacial Drift at Fox River Stone Company – St. Charles, IL – 100 feet of drift over

bedrock

Illinois River Valley

Prairie pothole ponds and marshes

Glacial erratic in Alberta

Exposed Loess Deposit

Glacial Landscape – Cross-section

Mean Monthly Temperatures – Urbana, Illinois

Cyclical climate and ecological change at Billy’s Lake, MN

• 10,000 to 8020 BP - jack pine, red pine forest with some oaks

• 8020 to 3400 BP - grassy prairies with sage (5000 to 4000 BP) and with oak after that

• 3400 to 1000 BP - deciduous forest - oak-grass to oak-birch to birch-hornbeam

• 1000 BP to present - pine forest - birch-white pine