REFLECTIONS

The world’s largest in a

Liverpool flat

A commentary on the experience of raising one of the

world’s largest , atlas.

Natalie Dugdale, 3rd Year Genetics BSc

he internet is a wonderful place; “From energy saving, eating machines they trans- T from same-day delivery of gro- ceries and clothing to purchasing a formed into wanderers, carefully evaluating every hot tub or a light aircraft, you can get hold of practically anything in no stem and leaf they could reach, before picking a time at all. In my case, I decided to place to weave a cocoon” purchase some newly hatched moth larvae from the world’s largest estingly, the changed now growing larger than males. By moth. I have kept many different substantially in appearance with seven weeks, I could barely keep up in my lifetime but have nev- almost every moult following the with replacing the number of leaves er delved into keeping before first. Unlike the vast majority of they were eating. The caterpillars now. The Atlas moth (Attacus atlas) moth , which shed their skin were massive and eating privet at a is the largest species of moth by four times, the Atlas moth grows so rate at which I had to replace wing surface area (1) and the second huge that it requires a fifth shed, branches every few hours and emp- largest by wingspan, second only to meaning it goes through six growth ty their tank of droppings twice a the White Witch (Thysania agrippi- phases known as “” through- day. Eventually, after a total of eight na). Atlas moths are a member of out its life as a . With the cater- weeks of gorging themselves (Figure the Saturniid family and along with pillars growing as large as 11.5 cm in 2), the caterpillars abruptly stopped several other subspecies, they in- eight weeks (1), they quickly started eating and their behaviour changed habit the forests of and South- a serious regime of eating. The drastically. From energy saving, , and recently, a one-bed green spiky larvae soon became eating machines they transformed flat in Liverpool. white and powdery-looking and had into wanderers, carefully evaluating doubled in size in less than a week. every stem and leaf they could At the end of July, I received a tiny In the space of five weeks, they had reach, before picking a place to cardboard box in the post, inside of grown to the length of my index weave a cocoon. Using the which was a petri dish containing a finger (Figure 1). Once they reached glands beneath their mouth, they few leaves of privet and ten tiny their fourth , a size difference spent the next two days carefully caterpillars. Barely a centimetre was becoming apparent between constructing intricately latticed silk long, prickly in appearance and pale the caterpillars and the sexes be- cocoons where they could safely green, it was merely days before came distinguishable, with females pupate inside. These structures they had their first moult. Inter-

Figure 1. in its 4th instar. Figure 2. Caterpillar in its 6th instar, Figure 3. Female removed hours before building her cocoon. from her silk cocoon for sexing.

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REFLECTIONS

Figure 4. Adult male Atlas moth resting on a Figure 5. Adult male Atlas moth resting on the author’s hands. window. were wrapped in leaves, well cam- ulus, so they went into a well venti- ries from their final instars (2), I ouflaged and protected by the silk lated and insulated box kept at a would like to think they were quick which solidified into a hard shell pleasant 18oC to wait out the winter. to warm to me as they may have around them. By the ninth week, my With a thermometer, a hot water had memories of my handling of enormous caterpillars had trans- bottle filled twice daily and regular them in the past with no ill conse- formed into pupa within enormous misting of the cocoons, it was appar- quence. This theory is probably a silk cocoons. Females have visibly ent that I had created an ideal envi- leap, of course, with their tame be- smaller antennae, even as pupa, ronment. On the sixth of December, haviour likely being learned (albeit allowing for easy sexing (Figure 3). I opened the box and was shocked quickly), or perhaps is simply typical to discover my first moth. Within 24 of this species. Aside from various butterfly and hours of the first emergence, a sec- moth websites and a few blogs, I After months of eating and growing ond male eclosed to join him (Figure struggled to find any solid infor- followed by months of pupating, the 4). With the largest of the two hav- mation on timings referring to com- adult moths live for a week or less. ing a wingspan of around 21.5 cm, plete metamorphosis from caterpil- They do next to no flying because these magnificent moths enjoyed lar to imago (adult moth). From the the effort is so great, and instead their final week of life fluttering information that I had gathered, I they conserve their energy in hope around a flat in Liverpool (Figure 5). initially expected my pupae would of coming across a mate during their Interestingly, the first two moths to eclose as moths within four weeks. short adulthood. I am incredibly eclose quickly became tame and As six weeks had passed and there grateful for being able to experience amicable. They climbed onto my were still no moths, I researched a the amazing life cycle of these won- finger voluntarily, of their own ac- little further and discovered that derful creatures and will definitely cord, and ceased all their defensive Atlas moth pupa are able to lie be raising more butterflies and tactics such as vibrating, flapping dormant and overwinter until condi- moths in the future. and spraying, all of which were com- tions became more suitable (3). All I monplace in the first days following knew was that they were still alive their emergence. Having found that and still responding to a touch stim- caterpillars are able to retain memo-

References 1 Association of Zoos and Aquariums. Atlas Moth (Attacus atlas). Available from: www.waza.org/en/zoo/choose-a-species/invertebrates/-and- millipedes/attacus-atlas [Accessed 13th December 2018] 2. Blackiston D J, Silva C E and Weiss M R. Retention of memory through metamorphosis: can a moth remember what it learned as a caterpillar? PLoS ONE 2008. 3(3): e1736 3. Worldwide Butterflies. Giant Atlas Moth (Attacus atlas) Cocoons. Available from: www.wwb.co.uk/giant-atlas-moth-attacus-atlas-cocoons%22 [Accessed 18th December 2018]

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