Of my top five most cited papers two are reviews, two are opinion pieces and one is a ‘real’ paper. I have written about the serendipitous event that resulted in my second most cited paper (Leather, 1988), but now it is the turn for Number 5 to make the headlines 🙂 Number 5 (Ward et al., 1998), is a ‘real’ paper in that it tests an hypothesis and is based on data. It would, however, almost certainly never have come into existence if my friend and former lab mate, Seamus Ward, hadn’t come to visit me at Silwood Park in the spring of 1997.
Seamus was in the year below me in Tony Dixon’s lab, originally taken on to work on the maple aphid, but it transpired that his life history traits were not suited to maintaining host plants and aphid cultures. Luckily it turned out that his true talents were in the area of theory and mathematical ecology; when you were talking to him about your aphids and what they were doing Seamus would sit there turning your description into equations. He thus ended up doing a PhD looking at life-history traits in aphids. I make no claims to being mathematically oriented, but do take a quiet pride in being pretty good at running practical experiments and this made for a good partnership in the group, in that Seamus would come to me when he needed some experimental support (real data). This was mutually beneficial and resulted in papers we would not necessarily have written otherwise (Leather et al., 1983; Ward et al., 1984).
Having not seen Seamus for some time, since finishing his post-doc in the mid-1980s, he had been based in Australia at the University of La Trobe, we were reminiscing about old times. I happened to mention that I had fairly recently examined one of Tony Dixon’s PhD students who had been working on the carrot-willow aphid, Cavariella aegopdii and the evolution of aphid life-cycles (e.g. Kundu & Dixon, 1993, 1995). This of course got us on to talking about host alternation and why, if it is so risky, (there were estimates of less than 1% surviving the journeys between hosts (Taylor, 1977)), some aphid species. albeit only 10%, had adopted that strategy. In another paper, Tony and Raj had suggested that even if only 1 in 10 000 survived
The words that inspired us – from Dixon & Kundu, 1994)
the migration from host to host, the high fecundities that host alternating aphids can achieve on their primary hosts (Leather & Dixon, 1981), would make it worthwhile (Dixon & Kundu, 1994). This got us thinking – how many aphids did actually make it and could we work it out? We discussed this for a while over a beer, (we were in the Silwood Bar at the time), and Seamus decided that what we needed were some data of numbers of aphids on the ground and the number of aphids in the air at the same time. As it happened, I had a ten-year run of bird cherry aphid data on their primary host, Prunus padus trees in Roslin Glen (Scotland) (from my bird cherry aphid side project) and as a subscriber to the Rothamsted Aphid Bulletins, I had in my office, copies of the weekly aphid bulletins for the nearest suction trap to Roslin Glen, East Craigs. This was enough for us to get started.
The bird cherry aphid side project data – still with me today and more analysis yet to be done 🙂
An example of the old paper version of the weekly aphid bulletin – I now subscribe electronically – a great resource https://insectsurvey.com/aphid-bulletin “The Rothamsted Insect Survey, a National Capability, is funded by the Biotechnology and Biological Sciences Research Council under the Core Capability Grant BBS/E/C/000J0200.”
The next day I started collating the field data and Seamus started to model. We were totally engrossed and kept at it all day, breaking only for meals and coffee. After dinner, armed with a bottle of whisky and bubbling with ideas we returned to the computer and Seamus started taking me through his model and fitting the data. Following the intricacies of the model was not easy for me and made my brain work so hard that my forehead started to sweat 🙂 Sometime near midnight, the bottle of whisky was empty, we had a working model and could put a figure on how many migrating aphids made it from the secondary host to the primary host – 0.6%. Now, all we needed to do was to get the official aphid and weather data from the East Craigs suction trap and write the paper, which with the collaboration of Richard Harrington and Jon Pickup of Rothamsted Research Station and East Craigs respectively, we successfully did, the paper being submitted in August 1997, and appearing in early 1998 (Ward et al., 1998). In case you were wondering how many bird cherry aphids make it from the secondary host back to the primary host, for every 1000 that take-off, 6 make it, so less than Roy Taylor’s estimate but more than the number that Raj and Tony suggested were needed to make host alternation viable.
So that is the booze and the sweat accounted for, but what about the blood? I had, as an undergraduate, become a regular blood donor and the day after our marathon data crunch, was my scheduled blood donation. That sunny morning, and somewhat hung-over, I walked across to the blood wagon, conveniently parked outside my office, made my donation and after my biscuit and cup of tea, headed back to my office. As I was passing the toilets, I felt the need for a pee, so nipped in to relieve myself, stood at the communal urinals, unzipped and started to pass water, as I did so, my blood pressure dipped and I started to faint, my last thought before I passed out was that I didn’t want to fall face down in the urinal gutter, so pushed away from the wall with one hand.
Not the actual urinal (they have long since been replaced) but this gives you the idea of what I didn’t want to fall into. Image source
I woke up some time later on the floor bleeding copiously from a head wound caused by me falling across one of the wash basins. To cut a long story short, I was rushed to the local hospital, my head repaired, and, as I had a post-donation faint, no longer allowed to donate blood. On the plus side, the paper has been very successful and I have an amusing after-dinner story to tell and the scar to prove it 🙂
Dixon, A.F.G. & Kundu, R. (1994) Ecology of host alternation in aphids. European Journal of Entomology, 91, 63-70.
Kundu, R. & Dixon, A.F.G. (1993) Do host alternating aphids know which plant they are on? Ecological Entomology, 18, 61-66.
Kundu, R. & Dixon, A.F.G. (1995) Evolution of complex life cycles in aphids. Journal of Animal Ecology, 64, 245-255.
Leather, S.R. & Dixon, A.F.G. (1981) Growth, survival and reproduction of the bird-cherry aphid, Rhopalosiphum padi, on it’s primary host. Annals of Applied Biology, 99, 115-118.
Leather, S.R. (1988) Size, reproductive potential and fecundity in insects: Things aren’t as simple as they seem. Oikos, 51, 386-389.
Leather, S.R., Ward, S.A. & Dixon, A.F.G. (1983) The effect of nutrient stress on life history parameters of the black bean aphid, Aphis fabae Scop. Oecologia, 57, 156-157.
Taylor, L.R. (1977) Migration and the spatial dynamics of an aphid, Myzus persicae. Journal of Animal Ecology, 46, 411-423.
Ward, S.A., Leather, S.R. & Dixon, A.F.G. (1984) Temperature prediction and the timing of sex in aphids. Oecologia, 62, 230-233.
Ward, S.A., Leather, S.R., Pickup, J. & Harrington, R. (1998) Mortality during dispersal and the cost of host-specificity in parasites: how many aphids find hosts? Journal of Animal Ecology, 67, 763-773.