Small is beautiful; microscopic can be deadly

This edited article about nature’s smallest animals and plants originally appeared in Look and Learn issue number 699 published on 7 June 1975.

Pygmy shrews

Our smallest native bird is the Goldcrest, but this is a giant compared with the world’s smallest bird the tiny Bee Humming Bird, found in Cuba and Ecuador. It gets its name because it is no bigger than a large bumble bee.

Its wings beat so fast that they are just a blur when it hovers in front of a tropical flower, its long beak dipping into the nectar in quest of nourishment. The adult females are slightly larger than the males.

Our smallest animal is the Pygmy Shrew, at two and one quarter inches, (57 mm), slightly smaller than the long-tailed Harvest Mouse. Even smaller is the Etruscan Shrew with a body length of only 1 and a half inches (38 mm) and reputed to be the smallest animal in the whole world.

Apart from animals, there are also a great number of microscopic insects. Some of these are so minute that they are scarcely visible to the naked eye.

The Dwarf Beetle, for instance, is small enough to pass through the eye of a small needle. The Small Blue Butterfly, less than 1 and a quarter inches (about 25 mm), across the wings, is the smallest British butterfly.

Unlike most of its kindred, it is only on the wing during the months of May and June.

The world’s smallest butterfly is the Dwarf Blue (Brephidium barberae) of South Africa. This delicate creature has a wing span of 0.55 in. (14 mm).

The smallest of all the known species of moths has one of the longest names. It is called Nepticula microtheriella and is found in Britain. It has a wing span of 0.11-0.15 in. (3-4 mm).

Turning briefly to plants, we discover that the smallest plant in the world is probably the Walphia whose flowers are only one-fiftieth of an inch, (about half a millimetre) in diameter.

Once we inspect the ocean, we find vast numbers of microscopic creatures floating in the water. Huge clumps of them make up the plankton on which most fish feed.

One of the very smallest of these vagrant organisms is a protozoan called Prymnesium. Sometimes under favourable circumstances, huge numbers are developed and it is then poisonous when eaten by fish.

Another kind of protozoa called Trypanosoma Brucei, is the parasite which causes African “sleeping sickness.”

The smallest fish in the world is the Philippine Goby, only one-third of an inch when fully grown. The smallest reptile is the Dwarf Gecko just 1 and a quarter inches (25 mm) long and, like most geckos, able to walk on the ceiling by means of suction pads on its feet.

The smallest of the crustaceans (aquatic animals with hard shells), are the water fleas which are found around the coasts of Great Britain. They come from the species Alonella and are so tiny that they almost defy measurement.

However it has been calculated that they measure about 0.0098 in. in length (0.25 mm).

Another of the midgets of the ocean are the smallest crabs in the world. They are called Pinnotheridae or pea crabs. These have been measured across the diameter of the shell at 0.25 in. (63 mm).