We collected the mass data of our mourning cloak (Nymphalis antiopa) pupae. After collecting and sexing all of our antiopa pupae and sorting them into two containers for each sex (see Sexing Nymphalis antiopa Pupae), we proceeded to weigh them to collect mass data. We were most interested in seeing the difference in mean mass between the sexes. After collecting the data, we did some basic statistics. Below are the summary stats and histograms, one stacked for both sexes plus one for each sex. Summary Satistics for Nymphalis antiopa Pupa Mass Data Mean Std Dev Median Min Max N Male 0.7880952381 0.06476047044 0.8 0.6 0.9 84 Female 0.8957746479 0.08006536565 0.9 0.7 1.1 71 All 0.8374193548 0.08983996384 0.8 0.6 1.1 155 Looking at the graphs first, the stacked male and female graph appears to be mostly unimodal and symmetric but slightly skewed right, with no outliers. The female graph is unimodal and very symmetric, almost a perfect normal curve. The male graph, on the other hand, is a little bit unusual, being slightly skewed left with a very high concentration in the center, o.8. The female masses are indeed higher the male's, having a mean of 0.896 g to the male's 0.788 g, over a decigram higher. A confidence interval for the difference in means is 0.085 to 0.131 (C=0.95), so clearly the difference is real. A two-sample t-test for the difference in means between the sexes also shows that the female mean mass is statistically significantly higher than the males (t = 9.2555; df = 153; p<0.0001). We also can't help but notice how shockingly little variation there is for the mass of both sexes, especially the male's, with standard deviations of just 0.0648 and 0.080 for males and females respectively. From what we've seen with most other larvae we have reared, the size variation is almost always very high, probably due to a plethora of random factors other than genetics while rearing - some larvae will just grow and grow while others hardly do at all, resulting in large and tiny pupae from the same rearings. It is usually only when larvae are thinned out to low densities, or if they are highly gregarious that pupae size tend to be more consistent. With the antiopas here, the pupae are very consistent in size and as larvae, they were extremely gregarious all the way up to pupation (they pupated in rows on the same branches), and they all grew at the same rate, all molting to the successive larval instars in near perfect synchrony. This suggests that competition between solitary larvae is a considerably large factor in their performance when reared in high densities. ![]() Authors Alan Liang
Comments
|
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 |