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Why are fish fish-shaped?
CrowdScience
Sep 30, 2022

There are over 30,000 species of fish – that’s more than all the species of amphibians, reptiles, birds and mammals combined. But despite the sheer diversity of life on Earth, we still tend to think of all fish in roughly the same way: with an oblong scaley body, a tail and pairs of fins. Why? And is that really the case?

Crowdscience listener and pet fish-owner Lauria asked us to dive into the depths of this aquatic world to investigate why fish are shaped the way they are. Do we just think that fish are all the same because we are land-dwelling?

Presenter Anand Jagatia makes a splash exploring the fascinating story of fish evolution, how they came to be such a different shape from mammals and even how some mammals have evolved to be more like fish.

Produced by Hannah Fisher and presented by Anand Jagatia for the BBC World Service.

Contributors: Professor Frank Fish – Professor of Biology, West Chester University Dr Carla McCabe - Lecturer in Sport & Exercise Biomechanics Dr Andrew Knapp – postdoctoral researcher at the Natural History Museum, London

Image: School of fish in shape of fish. Credit: Getty Images

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Jun 5, 2026
Do plants have personalities?

CrowdScience listener George is showing Alex Lathbridge around a small, dark, and extremely hot shed, just outside the city of Accra in Ghana. Inside are row after row of shelves, stacked high with bulging grow-bags. And out of some of them, gorgeous cascades of oyster mushrooms are bursting into bloom.

We’re on George’s mushroom farm, and he’s noticed something interesting. Even though the conditions in his grow-shed are tightly controlled – they have exactly the same food, water, and light as each other – nevertheless, they respond differently. Some are more vigorous than others, some bloom quicker, others last longer, and some are more tolerant when the conditions change. And this got George wondering. Could ‘brainless’ lifeforms like mushrooms, and plants, have different ‘personalities’? Do they experience the world differently, and live their lives differently from each other? Alex Lathbridge is on the case.

He visits the PGRRI, the Plant Genetic Resources Research Centre, for a quick lesson on genetic variation in the plant world. Plants are all different at the genetic level, and it’s those differences which can result in a tastier fruit, or a hardier crop. But would we call traits like these personality?

In the Minimal Intelligence Lab in the University of Murcia in Spain, Paco Calvo thinks that we absolutely should. He studies plant intelligence, and points Alex to a whole host of examples of plants being smart in ways which might surprise you. Each one is an individual, and if we can only slow down enough to appreciate them properly, we’d be able to understand them better too.

Back in Ghana, Alex meets plant physiologist Dr Acheampong Atta-Boateng, in the beautiful grounds of Aburi Botanical Gardens, to meet some of these plants for himself. And he discovers that there’s a whole world of smart, resilient, and resourceful little organisms in the plant world, full of personality, if you know where to look. Who needs a brain!?

Presenter: Alex Lathbridge

Producer: Emily Knight

Editor: Ben Motley

(Photo: Drawing of a face and smiling eyes on a sunflower flower - stock photo- Credit: Jose A. Bernat Bacete via Getty Images)


29min 16sec


Why are fish fish-shaped?

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