Thinking of the biological world draws our minds to terrestrial examples of grassy fields with sparse trees, shrubs, chirping birds, and small animals. Although some may recall images movies like Finding Nemo or The Little Mermaid offer, we often do not envision the ecosystem which covers most of the world’s surface: the aquatic ecosystem! Beneath the surface of water is a system full of diverse communities worthy of our attention. Eugene H. Kaplan takes us underwater on a journey to discover marine organisms and their physiology and aquatic habitats in his novel, Sensuous Seas: Tales of a Marine Biologist. He engages his readers in studying the aquatic ecosystem with illustrations and rich, vivid descriptions.

Themes described in Sensuous Seas closely relate to the ecology and evolution (a class I am taking this semester). One common concept in book is sexual selection for dimorphism. In Chapter 17, Kaplan explains that female fiddler crabs sexually select males with very large claws called the major chela, ranging 2-3 times its body size. Having such a large claw is morphologically disadvantageous to the male, thus highlighting the significance of mate selection in the biological world. Another theme is predatory relationships. Particularly in the light of natural selection, populations are selected for the best anatomy and survival mechanisms. Exemplified in Chapter 2 with the Great Jade Green Octopus, its beak is specialized to hook and tear away crab shells making prey easy to devour. Over generations, octopuses with beaks best fit for predation are naturally selected to dominate the gene pools, which explains their present beak shape. In view of the Red Queen Hypothesis introduced in the ecology course, the crabs may also have coevolved thicker and more complex shells to avoid being eaten by the octopus. Another theme Kaplan emphasizes is the relationship between species and habitat. As governed by evolution, species utilize their environmental conditions to maximize their benefits. The Samoan palolo worm’s breeding behavior in relation to the environment in Chapter 7 is a clear example. The female worms release egg-laden reproductive bodies into the sea which are met by the males’ sperm on the same night each year due to lunar cues. As discussed in the course, the Samoan palolo worm adapts to the environment to optimize reproduction with high fecundity, since newborns are at high risk of being eaten by predators. Recognizing common theories and their application enriches the reading experience and comprehension of the book.

Each chapter of Sensuous Seas: Tales of a Marine Biologist describes a particular organism’s unique physiology and Prof. Kaplan’s work experience with it. At the beginning of each chapter, Kaplan introduces the species in a creative and relatable way, either by sharing personal experiences or providing a fictitious scenario. For example, Chapter 6 opens with a date night where a man presents his girlfriend with flowers and the woman rushes to perfume herself before going out. Kaplan continues to describe how we use scent as a sexual instrument in our everyday lives, and he connects this behavior to the role of smell in fish, crab, and worm sexuality. After such introductions, the chapters are then divided into subsections focusing on principles unique to that species. Conceptually, Kaplan focuses on relationships the species has with its mates, predators or prey, and the environment. Referenced as “plates,” illustrations with figure descriptions are provided to highlight important visuals for comprehending the information. Plate 15 shows an image of a snail radula. The corresponding figure details its material make up, functionality in both carnivores in herbivores, the way it is used, and evolutionary variants. To conclude each chapter, Kaplan often makes large scale comments about the topic discussed or closes with a witty story related to the marine organism.