the following video provides a close-up view of the the development of 5 frog embryos.
11 days in 66 seconds:
more information on the making of this time-lapse video:
| Sony Cybershot F-717 & JG-RC2 intervalometer
2008-04-05 17:53 – 2008-04-16 11:04
x 14400 (1 second in the video equals 4 hours in real-time)
i found the frogspawn on april 1, and it couldn’t have been there for longer than 12 hours, because i did garden work around the pond just day before. recording started in the evening of april 4 (3 days later), but day one was discarded because (1) there was nothing going on except gas bubbles building up, and (2) there were some glitches in the photos.
in order to have the eggs stay at a precise point in the camera view, i suspended them from two thin crossing strands made of transparent plastic.
the total development time of the eggs until the little tadpoles emerged was 15 days. in my first time-lapse attempt, it took roughly 7 days.
this delay is most likely the result of a cold weather period in 2008. i estimate daytime temperatures to have been around 15 degrees celsius lower this year (approx. 20 degrees in 2005, just above freezing on some days in 2008).
since i used the 2005 video as a reference, i now have ridiculously high-quality data in my hands: a resolution of up to 1280 x 960 and 40 fps are possible (if you’re interested, drop me a line!).
as far as identification goes, i think it’s a european common frog (grasfrosch, rana temporaria).
update: prof. r. hofer (university of innsbruck) confirmed that the species name is correct.
there are individual photos (including a photo of one of the parent frogs), and an animated gif in the gallery: