Work Description

Research Overview:
This dataset consists of 11 linear external morphological measurements from 2,593 adult frog individuals from 757 species. We use these data to investigate patterns and rates of frog size and shape evolution. The measured traits are predictive of adult microhabitat use, diel activity patterns, locomotion, mating habitat, and diet. The results of this research will be available in an associated publication that is currently in preparation for peer-review. The data are made available so that other researchers can replicate the work or utilize the information for additional research.
The morphological measurements were collected by the lead investigator, Dr. Joanna G. Larson, with significant assistance from Abraham Weiner. All work occurred in the University of Michigan Museum of Zoology (UMMZ) Division of Reptiles and Amphibians in Ann Arbor, Michigan.

Methods:
This is a dataset of 11 external linear morphological measurements for individual frog specimens. The measurements are snout-vent length, head width, head length, internarial distance, interorbital distance, eye length, eye to naris distance, naris to snout distance, antebrachial length, femur length, and tibiofibula length. Additional details of how we defined these measurements are available in the "Definitions of Terms and Variables" section below. These measurements were selected because they are predictive of adult microhabitat use, diel activity patterns, locomotion, mating habitat, and diet. Measurements were taken using digital calipers and are reported in millimeters. The frog specimens are housed either in the University of Michigan Museum of Zoology (UMMZ) Division of Reptiles and Amphibians or the Museum of Natural History (MUSM) in Lima, Peru. We only measured adult frogs.

File Inventory:
This dataset includes one csv file. Each row contains information for a single frog specimen.

Definitions of Terms and Variables:
The following are explanations and definitions of the columns in the csv file:
Species: this is the species-level identification of the frog. This information is based on the identification in the museum catalog and not on identification by the dataset creators.
Catalog.number: this is the catalog number assigned to the specimen by the natural history collection in which it is permanently deposited. The vast majority of specimens are deposited in the University of Michigan Museum of Zoology (UMMZ) Division of Reptiles and Amphibians and these catalogue numbers are listed without the museum code. A small number of specimens are deposited in the Museum of Natural History in Lima, Peru and these specimens are indicated with the museum code "MUSM" in front of the catalog number. Catalog numbers are printed on the jars in which specimens are stored, as well as on paper tags that are tied to specimens. Some individual frogs (represented by a row) share the same catalog number. This occurs because the museum issued one catalog number to a group, aka a lot, of individuals of the same species. The individual within that lot to which the data (row) correspond can be determined by the value given in the Field.number category.
Field.number: some frogs were not assigned individual UMMZ catalog numbers and instead were grouped in jars with other frogs of the same species and assigned one catalog number. In order to be able to connect measurements to a specific specimen in future, we include this column to provide further identifying information. Often times frogs were given individual codes by the collecting researcher in the field and these are given in this column. These can be numbers, letters, or a combination of the two. These codes, like museum catalog codes, are usually printed on paper tags tied to the specimen. Sometimes these tags are metal. If "metal tag" is given in this column, it indicates that the specimen is the only individual in the jar with a metal tag tied to it and can thus be identified. This will permit other researchers to verify our data or collect additional data from the same specimen.
SVL: snout to vent length
Head.width: measured at the corners of the jaw
Head.length: measured from the jaw joint to the tip of the snout
Internarial: the distance between the nares
Interorbital: distance between the eyes, measured at the anterior corners
Eye.length: measured from the anterior corned to the posterior corner of the eyelids
Eye.naris: the distance from the anterior corner of the eye to the posterior edge of the naris on the same side of the body
Antebrachial.length: the length of the lower arm, measured from the wrist to the proximal end of the elbow
Femur.length: the length of the upper leg, measured from the distal edge of the knee to the vent
Tibio.fibula: the length of lower leg, measured from the heel to the proximal edge of the knee
Family: the taxonomic family to which the frog species is assigned