JEB desktop wallpaper calendar 2016

JEB desktop wallpaper calendar 2016

Seismic signals in a courting male jumping spider (Araneae: Salticidae)
Damian O. Elias, Andrew C. Mason, Wayne P. Maddison, Ronald R. Hoy
  1. Fig. 3.

    Effects of male abdominal immobilization on power spectra of different seismic signals. (A) Buzz signal; (B) scrape signal; (C) thump signal. Panels i-iii represent mean power spectra for one individual during the control, experimental and recovery treatments, respectively. Experimental treatment consisted of waxing the cephalothorax to the abdomen, rendering body segments immovable relative to each other. Recovery treatment consisted of removing the wax from the animal.

  2. Fig. 5.

    Effects of preventing male abdominal and cephalothorax contact on the power spectra of different seismic signals. (A) Buzz signal; (B) scrape signal; (C) thump signal. Panels i-iii represent mean power spectra for one individual during the control, experimental and recovery treatments, respectively. Experimental treatment consisted of waxing a piece of flexible foil to the cephalothorax and placing one end of the foil between the cephalothorax and abdomen. Recovery treatment consisted of removing the foil from between the cephalothorax and abdomen.

  3. Fig. 1.

    Seismic signals of courting male jumping spiders. (A) Sonogram of a seismic signal. (B) Oscillogram of seismic signals. Courtship can be divided into four distinct phases, with seismic signals occurring in phases 2-4. (C) Detail of oscillogram marked by the box in B. All three types of seismic signals can be observed: thumps [Th (red)], buzzes [Bz (green)] and scrapes [Sc (blue)]. Individual scrapes occur in groups consisting of multiple repeated scrapes [Sc G (yellow)]. Recordings made using a laser Doppler vibrometer.

  4. Fig. 2.

    Types of seismic signals. Top panels (i) show body positions, with numbers (1-5) illustrating movements of the forelegs and abdomen. Middle panels show (ii) the position of one of the forelegs (mm above the substrate) and (iii) the oscillograms of the seismic signals. Bottom panels (iv) show the frequency characteristics of the seismic signals. Panels ii-iv are shown in the same time scale, with numbers (1-5) corresponding to the body movements illustrated in panel i. (A) Thump signal. Front legs come down (1-2), contact the substrate and quickly move back up (2-3). Shortly afterwards the abdomen is pulled back and released, and the abdomen `rings' at 58.3 Hz (4-5). Thumps are broadband signals with peak frequencies at 203 Hz and 1203 Hz. Production of signal corresponds with the percussive contact of the front legs against the substrate (1-2) and movements of the abdomen (4-5). (B) Scrape signal. Abdomen moves up (1-2) and shortly afterwards the front legs come down (2-3). Scrapes occur in groups with a frequency of 5.7 Hz. Scrapes are broadband signals with peak frequencies at 230 Hz and 550 Hz. Production of seismic signal corresponds to movements of the abdomen. (C) Buzz signal. Front legs come down (1-2) as the abdomen oscillates at 65 Hz (1-2). This signal has a fundamental frequency at 65 Hz with several harmonic frequencies (130 Hz, 195 Hz and 260 Hz). Production of seismic signal corresponds with movements of the front legs and abdomen.

  5. Fig. 4.

    Effects of male abdominal immobilization on (A) thump, (B) scrape and (C) buzz seismic signals. Within individuals, peak intensities were normalized to the maximum intensity produced for all of the signal components. Normalized intensities were then averaged, and the relative dB difference between the treatments calculated. Graphs show relative dB difference between the treatments (control, experimental treatment and recovery) of all the individuals tested ± s.d. (N=5). Experimental treatments attenuated peak frequencies of all signals significantly (**P<0.001; Tukey post-hoc test with Bonferonni corrections). No significant differences were observed between control and recovery treatments.

  6. Fig. 6.

    Effects of preventing male abdominal and cephalothorax contact on (A) thump, (B) scrape and (C) buzz seismic signals. Within individuals, peak intensities were normalized to the maximum intensity produced for all of the signal components. Normalized intensities were then averaged, and the relative dB difference between the treatments calculated. Graphs show relative dB difference between the treatments (control, experimental treatment and recovery) of all the individuals tested ± s.d. (N=5). Experimental treatments attenuated peak frequencies of scrape and high-frequency (>500 Hz) ranges of thumps significantly (*P<0.05; Tukey post-hoc test with Bonferonni corrections). No significant differences were observed for buzz and low (<500 Hz)-frequency ranges of thumps. No significant differences were observed between control and recovery treatments.

  7. Fig. 7.

    Scanning electron micrograph (SEM) of cephalothorax and abdomen junction on (A) female and (B) male H. dossenus. (i) SEM of the posterior end of the head; (ii) SEM of the anterior end of the abdomen. F represents the ridged file found on male H. dossenus. S shows the location of the scrapers on the male.