Dr Justin Gerlach
I have supervised Natural Sciences undergraduates in Cambridge since 1995. I studied Zoology at Wadham College, Oxford and completed my DPhil there in 1994. That followed a very varied childhood: born in the Seychelles islands, with a very brief interlude in Cyprus, several years in Spain, finally in the UK, finishing my schooling at a very ordinary comprehensive in Northamptonshire.
Although most of my time is taken up with teaching I have also carried out research on a wide range of organisms and have a particular focus on saving species from extinction. My research interests can be summed up as saving species and ecosystems, discovering 'new' species and understanding their evolution. This is ecology in the very broadest sense: a synthesis of ecology, evolution and conservation biology, or why organisms and ecosystems are the way they are, and how they may change in the future. Within this I have worked on species interactions, population dynamics, behaviour, taxonomy, anatomy and embryology. This has mainly concentrated on islands in the Indian and Pacific Oceans where I have prevented the extinction of bats, tortoises and snails. The latter including bringing several species into a conservation breeding programme to prevent their complete extinction, and now successfully re-establishing them back in the wild. This is the very first time this has been achieved for any invertebrate; only 10 other animal species have been reintroduced successfully. Probably my favourite piece of research has been on Charles Darwin's beetle collection. My highest profile project has the discovery of a population of giant tortoises that hunt and eat sea-birds, something that really excited the world's media! Other species I have worked with have ranged from plants to bats, with most things in between, including tardigrades, insects, frogs and lizards. More detail can be found at http://islandbiodiversity.com/jg.htm. I am currently leading an initiative to identify the biodiversity across all Cambridge colleges and am developing several new projects around the world.
My current research and conservation interests are the Pacific island tree-snails (Partulidae) and giant tortoises. Historically these snails were the most important species radiation in the development of evolutionary thought but have largely been wiped out by the deliberate introduction of predators. My doctoral research was on the predators and in 1992, while researching these, I rescued some of the last surviving Partula snails. These have been breeding in zoos since then and their descendants started being released back into the wild in 2016. My research has led to new approaches to their conservation and since 2023 I have been leading the reintroduction of the snails back into their island homes. This achieved success in 2024 with the discovery of a re-established wild population of one species, 40 years after their extinction in the wild.
Giant tortoise research is centred around investigating the newly discovered and amazing hunting behaviour shown by tortoises on Fregate island, Seychelles. The tortoise work has also led to a new collaboration on the science of ageing.
Both the snail and tortoise research programmes include projects for Peterhouse students interested in studying ecology. I also have projects on palaeontology of St Helena island, sustainable agriculture in the Mediterranean and reconstructing fenland ecosystems using environmental DNA.
University Museum of Zoology, Cambridge - Academic Associate
Partulid Global Management Programme - scientific lead and in situ advisor
Cambridge Colleges Biodiversity Working Group - leader
Publications: A full list of my publications can be found at http://islandbiodiversity.com/jgpapers.htm
Most recent papers:
Gerlach, J. et al. 2024. Insect conservation on islands. In: Routledge Handbook of Insect Conservation.
Gerlach, J. 2024. Imperturbata griffithsi n.sp. and new records for Careoradula perelegans (E. von Martens 1898) in Seychelles (Mollusca: Gastropoda: Streptaxidae). Journal of Conchology 45(2): 234-238
Messenger, M., Greaves, M., Barclay, M.V., Gerlach, J. 2024. Charles Darwin’s early beetle collections: ‘Darwin’s beetle box’ and the Down House box. Journal of Natural History
Miller, G., Messenger, M., Zora, A. & Gerlach, J. 2023. How and why giant tortoises hunt birds and other animals. Testudo 9(5): 1-10
Gerlach, J., Griffiths, O. & Slapcinsky, J. 2022. Non-marine mollusks of the northern Narinda karst, north-western Madagascar. Bulletin of the Florida Museum of Natural History 60(1): 1-55
Zora, A. & Gerlach, J. 2021. Giant tortoises hunt and consume birds. Current Biology 13(16): PR989-990
Gerlach, J., Barker, G.M., Bick, C.S. et al. 2020. Negative impacts of invasive predators used as biological control agents against the pest snail Lissachatina fulica: the snail Euglandina 'rosea' and the flatworm Platydemus manokwari. Biological Invasions 23: 977-1031
