From sex change to cannibalism, the natural world is filled with wild mating strategies. In a new aquarium gallery titled Animal Attraction, the California Academy of Sciences delves into the science of sex, exploring the remarkable and often surprising techniques animals have developed for attracting mates and producing offspring. Visitors will encounter hermaphroditic banana slugs, barnacles that win the award for most well-endowed, cannibalistic praying mantises, parasitic anglerfish, and more than a dozen other creatures. Animal Attraction opens to the public on Saturday, February 11, 2012.
In a series of eighteen tanks, the exhibit will explore the concept that nothing in life is more important than reproductive success. Sex—the passing on and mixing of genes—drives evolution, and is responsible for much of what we consider beautiful in the natural world. If not for reproduction, plants wouldn’t bloom, birds wouldn’t sing, and deer wouldn’t sprout antlers. For the first time, the Academy will use iPads as exhibit labels, allowing visitors to zoom in on gorgeous images, watch videos of these strategies and behaviors in action, and guide their own digital explorations using interactive touch screens.
Truth can be stranger than fiction when it comes to reproductive strategies in the animal kingdom. When a male Ceratioid anglerfish finds a mate, he literally latches on and won’t let go. After biting into the female, the two fuse permanently, and the male will gradually atrophy until he’s nothing more than a pair of gonads. This extreme sexual dimorphism ensures that when the time is right, the female has one or more mates at the ready. For promiscuous garden snails, also part of the exhibit, males who successfully fire a “love dart” at a prospective partner double their chances of paternity.
The Art of Attraction
Cutting through the clutter is serious business when it comes time to attract a mate. Male bower birds of Australia construct bowers—elaborate display arenas decorated with twigs, leaves, and brightly colored objects from berries to bits of plastic—in which to woo females with their architectural prowess, flashy dances and vocalizations. The exhibit will include a colorful bower modeled after an example found in the wild.
Courtship is often at odds with survival. But the need to find and seduce a mate is one of the most powerful forces of evolution. In some species, like the praying mantis and salmon pink birdeater spider featured in the exhibit, females will sometimes devour males before, during or after copulation, a practice known as sexual cannibalism. For coral banded shrimp, also on display, the trick to a monogamous relationship is fierce aggression toward others of the same sex. Living in pairs, these shrimp will fight their mate’s potential suitors to the death. Visitors will also get up close and personal with a coconut octopus – for this animal, like other octopus species, sex is a tragic milestone. After mating, male octopuses die within months, and females will stop hunting in order to care for thousands of eggs, surviving just until they hatch.
Parental care in the animal kingdom ranges from intensive to practically non-existent, with numerous permutations in between. At the climax of courtship, male and female splashing tetras (small silver fish native to the Amazon) lock together and leap out of the water to lay and fertilize clutches of eggs on the undersides of leaves, away from the reach of predators. At that point, mom’s job is done, and dad hangs around for another 36-72 hours, using his tail to splash water on each egg cluster at one-minute intervals, until the eggs hatch and fall into the water, at which point parental care ceases. Depending on the species and environment, male Betta fish will care for their yet-to-hatch fry by constructing a bubble nest at the surface of the water, or by keeping the brood in his mouth for one to two weeks until they hatch.
The California Academy of Sciences is home to Steinhart Aquarium, Morrison Planetarium, Kimball Natural History Museum, and world-class research and education programs—all under one living roof. Admission to the Academy is: $29.95 for adults; $24.95 for youth ages 12 to 17, Seniors ages 65+ and students with valid ID; $19.95 for children ages 4 to 11; and free for children ages 3 and younger. Admission fees include all exhibits and shows. Hours are 9:30 am – 5:00 pm Monday – Saturday, and 11:00 am – 5:00 pm on Sunday. During peak periods, including some holiday weekends, an admission surcharge and extended hours may apply. Visit www.calacademy.org or call (415) 379-8000 for more.
* Thanks to the California Academy of Science News Department for this information.