Special exhibition at Kahaku reveals the surprising survival tactics of wild creatures

The National Museum of Nature and Science (Kahaku), NHK, and NHK Promotions are hosting the special exhibition "Super amazing world of Life" through October 12 at the premises of Kahaku in Ueno, Tokyo. In addition to specimens held by Kahaku and the latest research results, the exhibition introduces the surprising and moving world of living things using powerful imagery of creatures surviving in nature filmed by NHK's global nature program "Darwin's Amazing Animals."

Supervisor Hiroshi Namikawa, Head of the Division of Marine Invertebrates in the Department of Zoology, stated: "I would be glad if visitors learn that things humans take for granted, such as methods of movement and eating, are completely different in other animals, providing an opportunity to discover the diverse ecology of animals on Earth."

Earth today has diverse environments such as forests, grasslands, deserts, mountains, rivers, and oceans, and creatures have acquired unique abilities to survive in their respective environments. Some capture their surroundings with sharp senses, some obtain energy efficiently, some utilize their body size, and some move in diverse ways.

Focusing on such adaptive evolution, survival strategies, and the traits and functions acquired along with them, the special exhibition explains these survival techniques from six perspectives. Upon entering the venue, the first thing that catches the eye is a large display overlooking various global environments and the creatures living there. From there, it introduces creatures living in terrestrial, desert, forest, mountain, aerial, underground, sandy beach, aquatic, and lake/pond environments and how they have adapted to those environments. Of course, there are also displays of creatures living in cities. Visitors can feel firsthand that Earth has various living things across diverse environments.

Many creatures use their five senses in different ways from humans. In the exhibition, after learning the basic knowledge that sensation is what the brain perceives, the wonders of the five senses possessed by each creature are introduced. For example, it explains that while the eyes of squids and octopuses are similar in structure to human eyes, they are camera eyes that focus by moving the lens back and forth, as well as the mechanism of how the eyes of nocturnal mammals glow.

Regarding hearing, it introduces insects in which Johnston's organ functions as an ear, as well as bats and dolphins that communicate using ultrasound. "Eating" to obtain energy plays an important role for life, but diversity exists there as well. While there are snakes, frogs, marine life, and bees that use poison to prey, there are also antlions, spiders, and shoebills that wait patiently in ambush. Cheetahs and octopus species capture prey with swift movements, while anglerfish and alligator snapping turtles lure prey in.

Under Bergmann's rule, even among animals of the same lineage, smaller bodies lose heat more easily while larger bodies retain heat better, so those living in colder regions tend to be larger. The size differences among Sun bears, Asian black bears, Brown bears, and Polar bears can be explained by this. Extant sloths are small species with a body length under 1 meter, but the giant sloth Megatherium, which went extinct about 13,000 years ago, reached 6 meters in length and 4 tons in weight. In this exhibition, the fossil of Pyramiodontherium (4 meters in length, 1.8 tons in weight), a close relative of Megatherium, is also on display.

Many animals live while moving. However, some animals have chosen not to move or to depend on others. The pseudoscorpion Megachernes ryugadensis hitches a ride on mice, and the whale barnacle Coronula diadema hitches a ride on whales to move. The arrowhead scale insect moves as a newly born larva, but once it selects a living location on a leaf or fruit, it loses its legs and settles into a sessile life. Corals fix themselves to rocks and other surfaces. On the other hand, some coral species move on their own.

The exhibition also introduces the equipment and tent conditions used to film the ecology of these many creatures. Staff members of "Darwin's Amazing Animals" sometimes live in tents for weeks at a time. When asked, a filming staff member stated: "When spending days alone without being able to shoot anything, there are times when I don't even know what I'm doing. Even so, when a wonderful image is captured, my exhaustion disappears all at once, and it feels rewarding."