Spotlight on Steve Portugal

Spotlight on Steve Portugal

By Caroline Wood

“Go to work on an egg!”, so say the health experts. And, indeed, Steve Portugal does just that (although his interest in them goes beyond breakfast).
 
As the main organiser of the SEB “Cracking the Egg” Satellite meeting in Brighton this year, Steve is looking forward to welcoming egg researchers from around the world:  “Eggs have a lot to offer many fields of biology, and understanding them has applications to areas as diverse as food security, evolution, biomimicry, conservation and many more” he says. Now a lecturer of Animal Behaviour and Physiology at Royal Holloway College, London, Steve’s interest in avian research has persisted since his PhD and subsequent postdoc at the University of Birmingham.

Talking on egg shells

“Egg physiology is unique for each species and fine-tuned to their nest location and environment”, Steve says. “For example, Black Terns breed in very humid environments, such as marshes; consequently, the porosity of their eggshells has to be very high to allow sufficient gas exchange”. Using Natural History Museum specimens, part of Steve’s recent work has investigated common patterns in eggshell physiology and features that help species breed in extreme environments. For instance, microscopic analysis has revealed how cone-like nanostructures on Guillemot eggs render them with self-cleaning properties. “Guillemots live in dense colonies on cliffs and don’t make nests so it gets pretty messy”, Steve says. “The nanostructures make the eggshells hydrophobic, like a lotus leaf, so water and dirt stay as a droplet and fall off, rather than spreading all over the surface”. 

But eggs have a greater significance far beyond comparative physiology, as the satellite meeting will demonstrate. “The aim of the meeting is to bring together researchers from many different scientific fields, to talk about all things ‘egg’” says Steve. Interest in this field ranges widely and includes mimicking the properties of eggshell surfaces in colour technology and engineering applications. For example, the eggshell pigment protoporphyrin has been shown to have anti-microbial properties against gram-positive bacteria such as Staphyloccocus and Bacillus.

Furthermore, the egg is a model system for investigating how toxins are transferred through ecosystems, a famous example being the pesticide DDT. When applied in agricultural systems, the toxin accumulates in birds of prey, making the shells of their eggs thin and fragile, causing them to break during incubation. Meanwhile, with over 11 billion eggs consumed each year in the UK alone, they are a key asset for the food and agriculture business.  

‘Egging you on’

By bringing together researchers from all these areas and more, Steve hopes that this meeting will result in “new collaborations, multi-disciplinary grants submitted, and fresh ideas about what eggs have to offer in terms of biomimetic applications”. Subjects include reptile egg physiology, brood parasitology, egg hormones and egg-related citizen science projects.  Steve’s talk, meanwhile, will focus on how cuckoos mimic the eggshell colour of the hosts that they deceive, asking whether this mimicry is only skin deep or if it extends to the inside of the egg.  The meeting promises to be exciting, as Steve concludes: “You will be mind-blown by how amazing eggs truly are, and what they have to offer – you will never look at them the same way again”. 

When he’s not looking at all things egg-related, Steve enjoys feeding his obsessions for racket sports and natural history: “I especially love watching tennis, but if there’s no tennis on, I’m outside looking for wildlife….and food!” Which begs the question, how does Steve like his eggs? “I love mine poached”, he declares.