http://archive.fieldmuseum.org/tanzania/skin_instructions.asphttp://archive.fieldmuseum.org/tanzania/skull_instructions.asp

Skin Key Instructions The general strategy of a key is to, through a series of choices, narrow down the possibilities until you arrive at the correct identity of the specimen. START WITH "GENERAL" (unless you know what type of mammal you are examining). The user is presented with two illustrated descriptions about certain attributes of the specimen and must choose which description best matches the mammal skin or skull in question. Each pair of descriptions is designed to be "either-or". That is, it should be impossible for a given specimen to match both descriptions...it is either one or the other. For example: 1A) There are teeth in the skull. OR 1B) There are no teeth in the skull. WHEN MAKING A SELECTION, YOU CAN EITHER CLICK ON THE IMAGE OR THE SELECT BUTTON. Selecting which of the two choices best describes the specimen in hand will automatically take you to the next series of choices. The choices you make will ultimately lead you to a particular genus of mammal, which should be the correct identification of the specimen you are working with, if a) the key is properly,constructed and b) you used it carefully. When using the keys remember the following points: 1) The illustrations shown are for reference when referring to particular features. At times, the specimen you are trying to identify will not exactly match that of the specimens shown in the illustrations. Your specimen may have a different size or shape, and may have other features that do not match the illustration. This does not mean that you are making the wrong choice by choosing that option. Focus only on the aspect of the specimen to which the particular description refers. So, if the skull you are identifying has teeth, choose "1A) There are teeth in the skull", even if the teeth in your specimen look nothing like the teeth shown in the illustration. 2) Be mindful of the exact characteristics to which the key refers. Remember that a description in the key might list several criteria. Your specimen must match ALL criteria listed, so if only one of several criteria are not met, you should answer NO to that description. For example: 1A) A) Body without hair B) Ears long and pointed C),Snout elongate D) Nails on feet are spade shaped If ANY one of the four statements in the above description does not accurately describe the mammal in question you should not choose this option (even if all the other statements do accurately describe the specimen). 3) Pay close attention to EVERY word in a description: "Nails on the hind feet flattened" means on the HIND FEET, not the fore feet; "There are teeth in the upper jaw AND there are teeth in the lower jaw" is not the same thing as "There are teeth in the upper jaw OR there are teeth in the lower jaw". 4) These keys were designed for the identification of adult mammals only. While it may be possible to successfully identify some juvenile mammals with these keys, many others will be misidentified. To determine whether a skull is from an adult or juvenile specimen look at the last teeth in the upper jaw (A) and the sutures between the bones behind the palate (B). Teeth that are not fully erupted and sutures that are not fully fused indicate the animal is a juvenile. 5) If you reach the final identification, and the,illustrations do not look anything like the specimen you are trying to identify, start over (HOME-KEY) and pay close attention to each aspect of all of the descriptions. Because of the structure of these keys, you may be presented with the same choice more than once. 6) In Tanzania, as in other countries, new records of known mammal species are being documented all the time. New species to science are also still being discovered. It is possible that the specimen you are examining has not been recorded within Tanzania, and so is not included in this key. 7) At times you will be required to count the number of teeth on either side of a jaw. Just to be safe, count both sides of the jaw. If the number differs from one side of the jaw to the other, use the higher number. 8) At present the key stops at the level of genus, although in certain cases, such as aardvarks and rhinos, there is only one species in the genus. In cases where the genera are represented by more than one species, future additions are planned to allow the user to identify the specimen to species. 9) Some of the,characters used in these keys to define various genera may be ambiguous (especially with skin characters). The validity of some of these genera is in doubt and there is need for much more research to clear up some of the questions that remain regarding the taxonomy of these mammals. We hope you find these keys useful and enjoy using them!