Sound spectrograms (top), oscillograms (bottom), and associated power spectra (right), depicting 2 note calls for several Reithrodontomys mexicanus individuals. FFT size of 1024, Blackmann window, dynamic range of energy plots 120 dB. (A) ROM116844 male, power spectra of entire 1st note (1) and 2nd note (2). Horizontal arrows indicate the first 3 harmonic peaks, and and indicate subharmonic elements of the corresponding harmonics in A. These appear as full harmonics in both notes in B. Left bracket indicates harmonics blunted on note 1 (i), as compared to note 2 (II). (B) F48908 male, power spectra representing a 200 ms slice midpoint 1st note, and a 200 ms slice at midpoint 2nd note (midpoint indicated by arrowhead inserts). identifies a muted subharmonic below the 1st, or principal carrier. The harmonic carrying the frequency of greatest relative power changes between notes (indicated here by Roman Numerals I and II). (C) F48905 male, 2 independent calls, power spectra representing a 100 ms slice midpoint terminating 1/3 1st note, and the corresponding 100 ms slice midpoint terminating 1/3 2nd note of respective calls (midpoint indicated by arrowhead inserts on first call). Horizontal arrows point to harmonics in the first call blunted in the second call.
(A) Sound spectrograms (top), oscillograms (bottom), and associated power spectra (right) depicting 2 independent 2 note calls for R. mexicanus ROM117161 female, FFT size of 1024, Blackmann window, dynamic range of energy plots 120 dB. Power spectra represent 25 ms slices on the 1st note, and 2nd note, indicated by arrowhead inserts. Horizontal arrows point to corresponding harmonics (1, 2, 3), and subharmonic sidebands . Left bracket indicates harmonics blunted on note 1 (i), as compared to note 2 (II). (B) Comparative sound spectrograms (top), and oscillograms (bottom), for exemplar calls of (1) Peromyscus eremicus, (2) P. californicus, (3) O. leucogaster (all male). Examples taken from unpublished colony data. FFT size of 1024, Blackmann window.
Principal component analysis of call variables in the first carrier, with axes scaled according to sample variance explained by each component. Vector trajectories for each variable appear in the lower left, but center at zero. (A) mexicanus (Costa Rica), . Poas, Costa Rica (new species), . mexicanus from Ometepe, Nicaragua, . fulvescens (Texas). (B) , . Sexes tend to segregate on principal component 1, particularly when R. mexicanus is distinguished.
Principal component analysis of call variables among Peromyscus, Onychomys, and Reithrodontomys, with axes scaled according to sample variance explained by each component. Distributions in multivariate space represent the analyses of the 1st, or principal carrier data (A), and the analysis of the peak, or functional carrier data (B). californicus, . eremicus, . leucopus, . melanophrys, arenicola, . leucogaster, . fulvescens (Texas), mexicanus (Costa Rica), . mexicanus from Ometepe, Nicaragua, . Poas, Costa Rica (new species). , . (A) Reithrodontomys and Onychomys segregate from Peromyscus on principal component 1, represented by the ellipse. (B) The distribution of Reithrodontomys more diffuse considering peak carrier data, represented by the ellipse, with significant overlap with Peromyscus in multivariate space.
Spectrograms of vocalizations of Reithrodontomys mexicanus produced in same sex and opposite sex contact dyads, depicting (A) chirps and breathed notes, (B) broadband ultrasonic quaver (2 separate samples), (C) sample of ultrasonic quaver where the upper frequency maxima lies significantly above 95 kHz, taken from the same interaction as B, and (D) an example of breathed sounds, expanded on the temporal scale to illustrate the concordant presence of broad, frequency modulated notes, the upper frequency maxima of which lie above the upper 95 kHz limit our instrumentation can recover.
Eigen values of normalized data, percentage of total variation, and vector loading values of the parameters total duration, number of notes, minimum frequency, maximum frequency, peak frequency, and bandwidth for the first 2 principal components (PC1, PC2) in the principal components analysis for (A) the Reithrodontomys data set, and (B) the pooled Reithrodontomys and data sets.
Article metrics loading...
Full text loading...