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Dynamic dichotomous keys


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  • 1. NomenPlantor © The first dynamic dichotomous key The identification tool designed for worldwide use. Eficientech
  • 2. Overview of the identification systems
    • Traditional dichotomous keys
      • Taxonomic organization
    • Computerized keys
    • Dynamic dichotomous keys
  • 3. Traditional dichotomous keys Ex.: Familia Fagaceae
    • They are based on questions that must be answered by choosing one of two possible options.
    • There are a large number of keys generated by numerous authors.
    • They are portable and can be used easily in situ .
    • They are specifically designed for a closed list of species, unless they are organized taxonomically*. If there are problems adding species may even be necessary to reset.
    • If they are organized taxonomically, are difficult to use because it requires a high level of botanical knowledge.
    • If you can not answer all dichotomies , the identification can not be completed.
    • They are cumbersome to use.
  • 4. Taxonomic organization*
    • Facilitates the work of change and growth of a key.
    • The taxonomy is based on reproductive characters .
    • To manage reproductive characters a high knowledge of botany is required.
    • To display reproductive characters of the specimen is necessary, so it must to be in the proper phenological stage .
  • 5. Computerized keys Ex.: Alabama grasses
    • They are based on lists of characters to be selected and then filter the species or taxa to match them.
    • Is a very flexible and very agile tool if the amount of data is not very large. It can grow indefinitely .
    • When handling a large number of species, the list of characters can be very long. If it gets too becomes unwieldy .
    • Characters are defined for each taxon only as YES or NO .
    • All characters have same weight . By using the key you can choose characters that are not useful to discriminate the possible species.
    • No help to the user for identification is provided, due to the list format.
    • They are created only in author’s language .
    • They are created for an specific end-user level .
  • 6. Dynamic dichotomous keys (I) Ex.: Enviromental Educational Center "Solanillos"
    • It is an hybrid system between traditional dichotomous keys and computerized keys, taking the best of both.
    • They are based on questions to be answered by choosing one of two options , as in the classical dichotomous keys, so it provides a single question at each moment, there is not a long list of them.
    • They are based on lists of computerized characters and taxa to successive filters applied as computerized keys.
    • Characters can be defined for each taxon as YES, NO or POSSIBLE , which facilitates the use and management.
    • They are used to generate clusters of species, but clusters are not closed lists. Add or remove species is easy. In the dynamic key all data are interrelated and are reusable .
  • 7. Dynamic dichotomous keys (II)
    • They are designed to grow forever without becoming more difficult to use.
    • You can use non-reproductive and reproductive characters together.
    • Each character has a different weight according to the key you're using, and the system selects itself the most discriminating character each time.
    • It is not necessary to answer all dichotomies to get proper identification.
    • Each dichotomy involves a visual and textual user, making it a powerful educational tool .
    • You can select the end-user level of knowledge .
    • You can select the end-user language .
  • 8. Comparison between dichotomous keys
    • They are specifically designed for a closed list of species. There are problems to add new and may even be necessary to reset. Often the keys are not reusable .
    • The taxonomic organization allows key additions, but it increases difficulties since they are used for reproductive characters that not always are present and high botanical knowledge is required.
    • If you can’t answer all dichotomies , complete identification can’t be done.
    • They are portable but not very agile .
    • They are generated by grouping species (or taxa), but are not closed lists. Add or remove species is fast. In the dynamic key all data is interrelated and are reusable in future keys.
    • Taxonomic organization is not needed, so it is not essential to the use of reproductive characters. Then it is not necessary to have high knowledge of botany except in very specific key.
    • The reproductive and vegetative characters can be used together in the same key.
    • It is perfectly possible to identify either an specimen even without answering all the dichotomies .
    • They are not portable (by now) but are very agile .
  • 9. Main advantages of dynamic dichotomous keys (I)
    • They are easy to use even with a high number of species.
    • They can grow indefinitely without reducing its usability.
    • Textual and visual helps make it an excellent educational tool by itself.
    • Selecting the user level allows for adaptability to different use environments.
    • The language selection allows global use.
  • 10. Main advantages of dynamic dichotomous keys (II)
    • Species’ chorological data can generate geo-referenced keys in which key’s species dependent on the user's geographic position.
    • Custom species Hyperlinks allow associated data with expanding knowledge about themselves.
    • Characters Hyperlinks allow associated data with expanding knowledge of general botany.
    • The portability of dynamic keys will be improved with the availability of wireless devices connected to Internet.