Weaving through mazes of ancient-looking cabinets, the ever-present scent of mothballs permeating the air, one can only begin to comprehend the breadth and magnitude of the Museum of Manchester’s entomological collection of 2.5 million specimens. Much of it was donated or bequeathed from individual collections, and as such, allows a fascinating representation of the history of entomology around the world. By studying these collections, we can not only gain insight into the insects themselves, we can reveal peculiarities about the contexts in which they were collected. In today’s blog post, I would like to introduce you to a drawer of particular interest, originating from the collection of Mr. Joseph Sidebotham.

Josef Sidebotham, the frontispiece from Grindon’s (1886) memoir
Joseph Sidebotham (1824 – 1885) was a Mancunian businessman with a broad range of interests including, but certainly not limited to, natural history (Cook, 2015). A member of numerous scientific societies and highly esteemed in his community, his collection of Lepidoptera was donated to the Museum by his heirs in 1919, and included 1,900 species of mostly British origin. At first glance, they appear relatively consistent with other individual collections of the time. The butterflies are set with their wings depressed, nearly touching the bottom of the drawers, a style of mounting which was common until the 1860s. Despite being very aesthetically pleasing, only a few are labelled with dates or locations, as many personal collectors did not regard this information as vital.

The style of butterfly mounting in the Sidebotham collection; the Manchester Museum.
Upon closer inspection, elements of mystery begin to reveal themselves. The left-most column displays Orange-tip Butterflies (Anthocharis cardamines), which are a sexually dimorphic species, meaning that males and females look different. Male Orange-tip butterflies have (you guessed it) orange-tipped wings, while the females have more inconspicuous colouration. So, what are those two specimens in the middle, each with a single orange-tipped wing?

Drawer of butterflies from the Sidebotham collection; the Manchester Museum.

Two gynangromorph specimens of the Orange Tip (Anthocharis cardamines) from the collection of the Manchester Museum.
Those individuals are known as gynandromorphs, meaning they show both male and female characteristics (gyn – female, andro – male, morph – form). Resulting from errors during early development, they are uncommon in nature, but gynandromorphy has been documented in a wide range of insects (see Narita et al., 2010 for further details), spiders (e.g., Kaston, 1961) crustaceans (e.g., brine shrimps; see Campos-Ramos et al., 2006) (and even birds (Agate et al.,2003). It is most easily distinguished in sexually dimorphic species; however the pattern of male and female tissue can differ between individuals. Bilateral gynandromorphs, such as the Orange-tips above, have a left-right split of male and female characteristics. Individuals of the same species with a more random distribution of tissues, known as mosaic gynandromorphism, can also be found.
The matching pair of Orange-tips were likely a point of pride within Sidebotham’s collection, as their opposing colouration provides a striking example of gynandromorphism, and such specimens were often favoured by insect collectors due to their rarity and unusual appearance. Besides, these specimens seem to represent one of the oldest records of gynandromorphism in Lepidoptera (Narita et al., 2010). Now, they provide the Museum with not only an educational tool, but an intriguing little piece of history.

Jamie Burnett, the author of this post, with a drawer of butterflies from J. Sidebotham’s collection.
If you’d like to know more about Joseph Sidebotham, see online here and here.
If you’d like to know more about gynandromorphism in general, see online here and here.
If you’d like to know more about gynandromorphism in arthropods see online here.