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Wonderful life: the legacy of an

inspirational evolutionary

biologist

Mike Majerus Memorial Lecture

Professor Mike MajerusProfessor of EvolutionUniversity of Cambridge

Coccinella magnifica

Coccinella hieroglyphica

Evolution of colour pattern polymorphism

Mate choice in ladybirds

Evolutionary ecology of tropical butterflies

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Chilocorus bipustulatus

Evolution and ecology of insects

“Biological science must stand on its foundations in basic

observations of organisms in the field: what they do, when they do it,

why they do it, and how they have come to do it.”

Majerus, 1994

New Naturalist - Ladybirds Pandora neoaphidis and Coccinella septempunctata

“I also enjoy speculating... If my ideas and theories are subsequently put to the test by others who are caught up in a fascination of ladybirds...I will be delighted, whether my ideas are verified or refuted.”

Majerus, 1994

Engaging people in biological recording

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Pioneer of citizen science

Ladybird recording on-line in 2005

Ladybird “Top Trumps”

Ladybirds of Britain and Ireland (2011)

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Revised Naturalists’ Handbook

NIW: Ladybirds at London Zoo

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The Ladybird has Landed

“The Ladybird has Landed!

A new ladybird has arrived in Britain. But not just

any ladybird: this is Harmonia axyridis, the most invasive ladybird

on Earth.”

Press Release5th October 2004

2009-20102007-20082005-20062003-2004

Spread of the Harlequin ladybird

“The negative effects of H. axyridis on other aphidophages are likely to be the result of a complex range of interactions, with H. axyridis in general having a competitive edge through resource competition, intraguild predation and a more plastic phenotype. A more rapid development rate, continual breeding ability and lack of diapause requirement, efficient chemical defence and relatively large size would provide H. axyridis with a significant reproductive advantage over many native British species.”

Majerus et al. (2006)

One winner, one thousand losers

Majerus, M.E.N., Strawson, V. and Roy, H.E. (2006) The potential impacts of the arrival of the Harlequin ladybird, Harmonia axyridis (Pallas) (Coleoptera: Coccinellidae), in Britain. Ecological Entomology, 31, 207-215.

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Royal Society Summer Science Exhibition

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http://www.cedarcreek.umn.edu/

14-spot, Propylea 14-punctata© Bev Wigney

Harmonia axyridis as an intra-guild predator Spread of H. axyridis in Belgium and Britain

Methods

• “a well recorded one Km grid cell”

– more than two species have been recorded within it for three or more years across the time period

• Mixed-effect models

Declines in native ladybirds

Population data

Britain Belgium Switzerland

Species n Trend n Trend n Trend

Harmonia axyridis 1 824 Increasing 2 651 Increasing 1 344 Increasing

Adalia bipunctata 931 Decreasing 689 Decreasing 293 Decreasing

Total individuals (all native

species)

10 793 Decreasing 1 711 Decreasing 1 376 Decreasing

Number of native species 16 Decreasing 12 Decreasing 18 Decreasing

Roy, H.E., Adriaens, T., Isaac, N.J.B., Kenis, M., Onkelinx, T., San Martin, G., Brown, P.M.J., Hautier, L., Poland, R.L., Roy, D.B., Comont, R., Eschen, R., Frost, R., Zindel, R., Van Vlaenderen, J., Nedvěd, O., Ravn, H.P., Grégoire, J-C., de Biseau, J-C. and Maes, D. (2012) Invasive alien predator causes rapid declines of native European ladybirds. Diversity and DistributionsDOI: 10.1111/j.1472-4642.2012.00883.x

Rapid and dramatic declines

Rapid, dramatic and ongoing declines in the distribution of formerly common and widespread native ladybirds in Belgium and Britain following the arrival of Harmoniaaxyridis

Five (Belgium) and seven (Britain) of eight species studied show substantial declines attributable to the arrival of H. axyridis

Trends in ladybird abundance revealed similar patterns of declines across three countries

Rapid biotic homogenisation at large-scale could impact on the resilience of ecosystems and severely diminish the services they deliver

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Biotic homogenisation in the words

of Mike

“I have an unnerving nagging at the back of my mind that faunal and floral homogenisation is among the most detrimental of the ways in which humanity is affecting the Earth.”

“This risk of homogenisation is, as yet, recognised by few. However, the evidence of habitat homogenisation is obvious.”

“The dominant species associated with these homogeneous habitats tend to be the same over large geographic areas. More often than not they are generalists.”

Majerus, 1994

It’s been a wonderful life…

Mike Majerus and all those he has inspired and continues to inspire around

the world