We collected the pupa mass data from the Smerinthus ophthalmica pupae of our summer 2017 rearing. Today concludes our mass rearing of Smerinthus ophthalmica this summer as all larvae have now pupated. yes, it's quite terrifying just how many pupae we have now if you just look at the pictures. We'll be in for a real disaster if they don't diapause and all start eclosing right before we head off to Ithaca. For now, we've transferred them all to a large tub and spread them out evenly and will be checking for signs of development when we expect them to eclose (if not diapausing, probably in a week). So, on to the mass data. Over the past two weeks, we've been actively recording the masses of every viable pupae the day it pupated and have just entered it all in a spreadsheet today. The total count for our rearing in 275 pupae, 141 male and 134 female (though just today we discovered two were dead, but since we already recorded their masses they are included in the data). Below are summary statistics and a stacked histogram showing the frequency distribution of pupa mass by sex, as well as singular histograms for each sex. Summary Statistics for Smerinthus ophthalmica Pupa Mass (Summer 2017) Mean Std Dev Median Min Max N Male 1.966666667 0.2316606714 2.0 1.2 2.6 141 Female 2.28880597 0.3147168313 2.3 1.5 3.2 134 All 2.123636364 0.3186213667 2.1 1.2 3.2 275 Though a statistician could definitely do quite a bit of analysis here, the main things to notice are that the distribution of the combined female and male data set is nearly unimodal and symmetric with a few outliers on each end. Oddly, however, we should be expecting a bimodal distribution here because through performing a two-sample t-test, we found that the difference of means between female and male pupa was extremely statistically significant (t = 9.7001; df = 273; p<0.0001). When looking at the histograms for the individual sexes, the distribution for both are more or less unimodal or symmetric, especially the male's, so nothing unusual there. If it is like the case with human height, then perhaps despite that the difference between masses of the individual sexes is significant, the variation in the distribution of both are so great that the combined graph cannot illustrate the difference, hence its lack of bimodality. But then again, we're not statisticians.... Comparison with our spring rearing: Another point of interest in collecting all this mass data is comparing to mass data from previous rearings. Below are the summary statistics and histogram for our spring 2017 rearing. Summary Statistics for Smerinthus ophthalmica Pupa Mass (Spring 2017) Mean Std Dev Median Min Max N Male 2.481818182 0.2358736179 2.4 2.1 2.9 11 Female 3.02 0.2936362073 3.05 2.5 3.4 10 All 2.738095238 0.377460184 2.7 2.1 3.4 21 Though the sample size was much smaller, it is quite obvious that the spring masses are higher on average. The difference of means between spring and summer pupae is 0.614±0.144 (C=0.95), for male pupae is 0.515±0.144 (C=0.95), and for female pupae is 0.731±0.203 (C=0.95). A two-sample t-test also showed that the difference of means between the two rearings was extremely statistically significant (t = 8.4037, df = 294, p<0.0001). The incredible size difference between our two rearings is certainly due largely to the severe overcrowding and poorer leaf quality (leaves were more mature later in the season and keeping cuttings fresh with water tubes became impractical) in our summer rearing which greatly reduced the average mass of the pupae. Anyone who has reared larvae in mass quantities has experienced this. Other factors could have been genetics, which seems to play a surprisingly large role in the size of these and similar moths, as we have seen quite a large size difference between different lineages of larvae in the past (no statistical evidence, though). The parents of the larvae in the summer rearing were those from the spring rearing, but the majority of the parents were some of the smallest of the brood (we tried to pair large ones, but the timing of the eclosions made this difficult). The only decently large pairing we managed to obtain was the last one, which produced the youngest larvae of our summer rearing, which, we indeed noticed seemed larger than the older ones (the 3.1 and 3.2 females and 2.5 and 2.6 males were among of the last to pupate). Thus, the smaller sized pupae seen in the summer rearing could be partly explained by genetics due to the bottlenecking of "large" genes from our spring rearing. And finally, the last little thing to discuss for our mass data: the exuviae. Over the weeks, we collected every single exuviae shed by the prepupae upon their pupation out of curiosity to see just how much mass loss from prepupa to pupa is accounted for by the exuviae. Because a single piece is too light to register on the scale, we consolidated all the exuviae in a single petri dish and tared the collective mass which read 14.7 g. The total mass of the 275 pupae we recorded is 584 g. This means that the prepupa loses about 0.0535 g, or 0.0246% of their mass upon pupation! Now that's quite a thick cuticle they got there! ![]() Authors Alan 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 |