 Today we learned just what a confused newly molted anise swallowtail (Papilio zelicaon) larva can be capable of. . . We have always noted that in insect species where cast off cuticle is routinely eaten, there is some sort of psychological change that occurs immediately after molting that prompts them to look for the skin, recognize that it is skin, and eat it. The behavior seems purely instinctive. We have found, with observational experimentation, that putting skins at the mouth of these newly molted insects creates an automatic response to feed on it. The skins need not be its own. Today, we were playing around with a newly molted anise swallowtail (Papilio zelicaon) fifth instar that had not yet eaten its skin. We carefully placed the skin at its mouth to prompt it to start feeding on it while it was still in the "skin-eating mode". After it finished the skin, we continued to place more skins left behind by a few of the other larvae that molted. As long as we kept putting more skin there, it continued to feed, thinking that it still had not finished. It appeared to like the stuff very much. . . it is probably quite nutritious. Eventually, after finishing its fourth skin, we got a sick idea to try to see if it would be also willing to feed on larvae. We had a lot of first instars on hand that we thought couldn't be much different than the skin that it was already eating. The main other constituents are blood, which is obviously edible (in fact, injured larvae instinctively look for the blood to try to drink it up), and gut which contains partially digested food matter and fluids (which disturbed larvae sometimes regurgitate and then drink back up) and is also edible. Both of these things should actually be in more easily digestible forms than eating leaves and would probably be more efficiently assimilated by the body. This and many other reasons are why cannibalism is so great among meat-eating organisms and why meat is more nutritionally viable than plant matter. We put the first instar onto a skin and got it to start eating the skin first. When it got to the first instar, the first instar started thrashing around violently as it was getting attacked and the fifth instar backed off. Eventually, however, it started biting through the first instar from its end (the head capsule is difficult to bite) and ate the whole thing happily. . . We're not sure if it even realized. After that, we gave it another one, along with a sixth skin, which is also ate. Perhaps it will have some strange poops after this meal. After the second first instar, it started to lose its appetite and we put it back onto the fennel. Obviously, it would not be a good idea to try to sustain it only on skins and larva and it would most likely reject them once it gets out of the skin-eating mode. But this was still an amusing (okay, maybe more disturbing than anything else) experiment. Perhaps this larva will perform better than it would have if it hadn't eaten all this stuff.  Authors
Brian Liang
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Timeline 2012–2017
Albany, California This timeline is a series of daily posts recording our observations on and experiences with various insects in Albany California and surrounding areas, from 2012-2017. Since we did not publish this site until 2016, posts before that were constructed retroactively. Starting in August 2017, we moved to Ithaca, New York; posts from there on can be viewed at Timeline 2017-present: Ithaca, New York. Archives (1,011)
August 2017 (49) July 2017 (121) June 2017 (79) May 2017 (77) April 2017 (91) March 2017 (35) February 2017 (12) January 2017 (10) December 2016 (12) November 2016 (26) October 2016 (49) September 2016 (84) August 2016 (94) July 2016 (99) June 2016 (53) May 2016 (21) April 2016 (4) January 2016 (1) August 2015 (3) July 2015 (3) June 2015 (2) June 2014 (3) May 2014 (1) April 2014 (3) March 2014 (3) December 2013 (2) November 2013 (2) October 2013 (5) September 2013 (11) August 2013 (15) July 2013 (9) June 2013 (5) May 2013 (4) April 2013 (3) March 2013 (2) February 2013 (3) January 2013 (2) December 2012 (2) November 2012 (1) October 2012 (2) September 2012 (2) August 2012 (5) July 2012 (1) June 2012 (1) Authors
Full Species List (Alphabetical by scientific name) Note: - Not every species we encounter is necessarily presented on this site, rather a selection of those that were of particular interest to us and that we felt were worth documenting. - We can't guarantee that all species have been identified accurately, particularly taxa we are not as familiar with. Lepidoptera Actias luna Adelpha californica Agraulis vanillae Allancastria cerisyi Antheraea mylitta Antheraea polyphemus Anthocharis sara Argema mimosae Attacus atlas Battus philenor hirsuta Bombyx mori Caligo atreus Callosamia promethea Coenonympha tullia california Citheronia regalis Cricula trifenestrata Danaus plexippus Eacles imperialis Erynnis tristis Estigmene acrea Eumorpha achemon Eupackardia calleta Furcula cinereoides Heliconius erato Heliconius hecale Heliconius sapho Heliconius sara Hyalophora cecropia Hyalophora columbia Hyalophora euryalus Hylephila phyleus Hyles lineata Junonia coenia Langia zenzeroides formosana Lophocampa maculata Manduca sexta Morpho peleides Nymphalis antiopa Orgyia vetusta Orthosia hibisci quenquefasciata Pachysphinx modesta Papilio cresphontes Papilio eurymedon Papilio glaucus Papilio machaon oregonius Papilio multicaudata Papilio polyxenes asterius Papilio rumiko Papilio rutulus Papilio zelicaon Phyciodes mylitta Phyciodes pulchella Pieris rapae Plejebus acmon Poanes melane Polites sabuleti Polygonia satyrus Pyrgus communis Rothschildia jacobaeae Samia cynthia advena Samia ricini Smerinthus cerisyi Smerinthus ophthalmica Strymon melinus Trichoplusia ni Uresephita reversalis Vanessa annabella Vanessa atalanta Vanessa cardui Unidentified Lepidoptera Hybrids Papilio glaucus × Papilio rutulus Papilio polyxenes asterius × Papilio zelicaon Orthoptera Melanoplus devastator Phaneroptera nana Pristoceuthophilus pacificus Scudderia mexicana Trimerotropis pallidipennis Phasmatodea Carausius morosus Phyllium giganteum Mantodea Mantis religiosa Phyllocrania paradoxa Hymenoptera Apis mellifera Bombus vosnesenskii Brachymeria ovata Linepithema humile Pediobius sp. Polistes dominula Xylocopa varipuncta Unidentified Diptera Lucilia sericata Unidentified Hemiptera Brochymena sp. Leptoglossus sp. Nezara viridula Odonata Argia vivida Libellula croceipennis Coleoptera Coccinella septempunctata Cycloneda polita Diabrotica undecimpunctata Hippodamia convergens Araneae (Class: Arachnida) Araneus diadematus Phidippus johnsoni |
