Tiny Baetis mayflies are perhaps the most commonly encountered and imitated by anglers on all American trout streams due to their great abundance, widespread distribution, and trout-friendly emergence habits.
John Lloyd documented just what we watched in the video (Lloyd, J.T. 1921. The biology of North American caddis fly larvae. Bulletin of the LLoyd Library of Botany, Pharmacy and Materia Medica, Entomological Series, No. 1 21:1-124.)
http://deepblue.lib.umich.edu/handle/2027.42/32923].
To briefly summarize the Merrill paper (who studied about 30 species in 10 families from NA) those papers, the majority, but not all, caddis are able to "recognize" their case when it is put in front of them, and so will re-enter the case. Sometimes rapidly and repeatedly like the phryganeids Jason filmed.
One shelter available to two critters programmed to avoid exposure as a defense mechanism? It seems to me a circular response was stimulated by the artificial isolation in the tray.
It would seem to me that if we assume the instinctive character of survival then the video proof would counter that assumption simply by drawing attention to itself under the watchful eye of the trout.
???????????
John Lloyd documented just what we watched in the video (Lloyd, J.T. 1921. The biology of North American caddis fly larvae. Bulletin of the LLoyd Library of Botany, Pharmacy and Materia Medica, Entomological Series, No. 1 21:1-124.)
it would be alot cheaper if ya just bought an old musty copy
Ain't the internet grand ;?)