lack precision. This is because soils are not as sensitive as meteorological instruments for recording climatic conditions. However, in a fairly broad category, climate can be interpreted from the sensitive features found in soils. One of the most large-scale influences regarding the classification of climate was created in 1918, then modified over two decades by the German meteorologist Vladimir Köppen (Trewartha 1982). He proposed there are five main climate groups (Köppen climate classification), each corresponding to the main types of terrestrial vegetation. Each climate type is designated by letters, with upper-case letters referring to the main climate groups and lower-case letters referring to subsidiary climatic features. (Retallack 2001) Organisms Large plants are only part of the organisms that play a role in soil formation. For example, fungi are closely associated with the roots of many vascular plants by making available nutrients like nitrogen and phosphorus in a way that their host plants can utilize, and play an important role in returning organic matter to the soil by decomposing leaf litter. The list of organisms that interact with, and affect, soil is extensive, and it is these interactions that allow for the presence of paleosols to be inferred. Not only can particular organisms be interpreted from paleosols, but also ancient ecosystems. The soil interaction of plants is different from community to community. They each have distinct patterns of root traces, soil structure, and overall profile form. Identifying these features is useful for providing an overall assessment of the influence past organisms had on any particular paleosol. However, qualifying these general effects of organism activity can be difficult because the level of their expression is as related to their nature as it is to the amount of time available for soil formation. Even when fossils that are found in paleosols are understood, much more can be learned regarding their preservation, ecology, and evolution by studying the paleosols they inhabited. A fossilized footprint, burrow, or coprolite (fossil feces), are examples of trace fossils (ichnofossils). These trace fossils do not represent any physical part of an organism, but rather evidence of an organism's activity within its environment. Whereas a bone, leaf, or stem might provide enough information to positively identify a particular species, trace fossils rarely allow for such a precise identification. However, unlike fossilized body parts which can be affected by many variables, trace fossils are not often transported away and are usually