Volume 39, Number 1,
October 1992:
Springtails

Text-only version

ABOUT THIS ISSUE
- about KSN
- about the author

IN THIS ISSUE
- part 1
- part 2
- part 3
- part 4
- part 5
- part 6
- part 7
- part 8
- part 9
- part 10

SLIDESHOW
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Springtails
by Kenneth Christiansen

Collembola are a very ancient group and the very first fossil specimens are from the middle Devonian period about 380 million years ago. Some of these forms do not belong to any modern group of Collembola but are members of a now extinct genus. Since this genus is a highly specialized one, it implies that Collembola were around a very long time before the Devonian. Springtails are also very persistent through evolutionary time. The first really good fossils of Collembola are from Oligocene amber about 33 million years ago. These species all belong to genera still around. Most of the species we see today were probably here long before we arrived on the scene, and many will probably be here long after we have gone.

You may ask if the Collembola are all this wild and wonderful, why do most people know so little about them? The first and foremost answer is that they are so small. I have always noted that even when trained cave biologists go into caves they find Collembola only one of three times where I find them when I go into the same caves. I feel that it is certain that if Collembola were the size of cats there would be whole zoos devoted to them.

A second reason for general ignorance is the fact that they are so small that it takes special techniques to collect them. One easy way to collect is to make a simple aspirator such as shown in Figure 22. You will need a small jar filled with alcohol containing a number of small vials, a pair of small pincers, cotton and an aspirator. When you wish to make a collection you place a small vial, about 1/2 full of alcohol, in the large vial or tube as shown. To collect the specimen you point the intake at the springtail about 1 mm away and suck on the other tube sharply. The creatures stick in the alcohol in the small vial. After you have made all the collections you wish, remove the vial, put a label on it and use the pincers to plug it with cotton. Put this in the jar and take out another vial to start over. For examination under the compound microscope the animals can be mounted in Faure's medium or any other clearing mounting medium.

A third reason for people ignoring Collembola is that the good things they do for us are easy to ignore, and they really don't do much bad to us. The important role springtails have in recycling organic debris in the soil and probably even more important role in maintaining fungal and nematode concentrations favorable to plant growth is poorly studied. There are a few serious agricultural pests, most notable is the beautiful Lucerne Flea (Sminthurus viridis) in New Zealand and Australia which is a serious pest of alfalfa, but by-and-large Collembola are a harmless lot. There are no parasitic springtails of any sort, and the few examples of them infesting humans have been due to very peculiar circumstances. One of the most remarkable ones was a man who, collecting Collembola extensively in the Arctic with a leaky aspirator, manages to get a culture living in his nasal passages! He discovered this when Collembola started showing up on his handkerchief after he blew his nose. Other people who work around horses occasionally find Collembola living in their hair, but there have been few reports of this in recent years.

A fourth reason for general ignorance is that we have not found very many ways to use them so far. There have been some fairly successful attempts to use the Collembola fauna of the soil as indicators of the agricultural potential; this is used to some extent in Europe. Some springtails are extremely resistant to insecticides and some such as Folsomia candida can even digest DDT. It has been suggested that they might be used to decontaminate areas infested with these poisons but no extensive attempts have been made. Recent discoveries have shown that springtails are important in keeping root nematodes under control, and reducing infection by some soil borne pathogenic fungi. Again research into these areas is in very early stages. It is distinctly possible that we will make much greater use of them in the future.

In any case Collembola are really interesting animals and can be found everywhere. Next time you see little white creatures in a flower pot or tiny active blue-black specks on a patch of snow in a woods or on a tide pool, get a hand lens and look at them carefully. Better yet, start tearing off loose moist bark or turning over rocks and look for their scurrying bodies. Collect some and start identifying them. Soil Biology Guide published by Wiley and edited by Daniel Dindal, which should be available at any well equipped library, should enable you to do this.