Figure 7

Independent movements in the female Drosophila reproductive tract. Ai. Simultaneous recording from 4 ovarioles, the peritoneal sheath (PS), oviduct and spermatheca, plus a stationary control. In this preparation, the bases of the two ovaries and uterus lie on the microscope slide – the spermatheca and oviducts are free to move within the saline, while the ovarioles contract within the ovary. Video recorded at 15 frames/second; only the position of the light/dark boundary is shown. Aii. Part of the record is shown expanded. Note that the spermatheca has the largest movement, when its duct uncurls for 5–6 seconds at a time. The movement in the spermatheca has a small, gradual pull on the PS and oviduct, but small, higher frequency waves are also seen in these organs. The oviduct trace shows that its contractions occur at random with respect to those of the spermatheca, sometimes occurring before, at other times during or after those of the spermatheca. Each of the ovarioles has independent activity within the ovary, ranging from fast and frequent to occasional and erratic. Note that, at the PS recording site (see Fig. 7C), the PS can be seen as a lighter colour fringe, while on the other ovary control recordings were taken where the peritoneal sheath is stretched tautly over the eggs and so no PS waves were apparent. B. Fast Fourier transforms of the data shown in A, plotting the power density from 2 to 300 contractions/minute. Although the raw FFT output extended below 2 contractions/minute, this corresponds to slow drift in the preparation rather than biological activity. Virtually no energy occurs above 60 contractions/minute (1 Hz), so recording at 2 frames/second captures the movement faithfully. Note that the ovarioles all have peaks at different frequencies. For the spermatheca, the nearly square waveform means that the main peak is accompanied by several side bands. C. The first frame of the video, showing the position at which the recordings were taken. The video is available at reduced sample rate in QuickTime format [see Additional file 1] or in other formats [50]. Scalebar: 250 μm.