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Flies may bite and wasps may sting. With their bites, flies and mosquitoes may transmit diseases
that kill millions of people. The sting of a single wasp may kill someone who is allergic to
the wasp's venom. And even if kills by fly-transmitted diseases or allergic reactions to a wasp's
sting may be the exception rather than the rule, the presence of flies and wasps is often
irritating enough. For such reasons, flies and wasps are broadly seen as a nuisance we have to live
with.
Biting or stinging is utterly alien to butterflies. The very idea of butterflies killing people
is so stupendously ridiculous that, even in one's wildest nightmare, one can hardly imagine such
thoughts. True enough, some species may inflict damage on crop harvests, but this damage is done
by the caterpillar, not the butterfly. In contrast to flies and wasps, butterflies bring joy to
people because of their beautiful colors, their association with flowers -rather than dung or
carrion-, and with lovely sunshine and springtime. The naturalist Bates characterised butterflies
as 'creatures selected as the types of airiness and frivolity,' a qualification no way meant
derogatory. Butterflies thus associate with beauty and positive emotions. Butterflies are probably
the most beloved of all insects.
If butterflies are so beloved, they must be easily recognisable - else there would be little
to love. And indeed they are. Four sizable wings make them look rather big - even
though the wings are just virtually weightless membranes. The wings carry scales - flattened
hairs that cover the membranes like tiles cover a roof. This photograph shows small parts
of a Painted Lady's wings. Two structures draw attention. First, the rods that transect the
photograph are the veins that give the membranes strength. Second, the scales are the just
visible small almost square tiles. Each scale has a single color, but because different scales
may be differently colored, very nice patterns may be perceived if the butterfly is observed
from a normal distance. If you rub the wing of a butterfly with your finger, you will see
colored 'dust' on your finger - this dust are the scales.
Another important feature of butterflies and moth is their tongue, used to imbibe fluids,
typically nectar from flowers. Alternatively, butterflies may drink water, like in this
photograph, while you can sometimes observe butterflies even feeding on carrion! The tongue
is formed from highly modified jaws, so butterflies cannot bite even if they wanted.
So far I lumped butterflies together with moths and indeed they form a natural group, known as
the Lepidoptera - from the Greek lepidos = scale and ptera = wings. Within this order,
butterflies form again a natural group - which is to say that all butterflies share a common
ancestor, and all descendants from that ancestor are butterflies. Moths do not form a natural
group in this sense. But the term is quite useful for everyday use, so I won't bother too much
about taxonomical niceties.
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A rough criterion to distinguish butterflies from the rest is the time of activity. While
most moths are nocturnal, butterflies are typically diurnal. More reliable to distinguish
butterflies from moth is the shape of the antennae: butterflies have threadlike antenna
with a little club at the end. There are enough moths that are diurnally active, but the shape
of their antennae is rather different. The shape of their wings is different, too, so it is
really easy to tell butterflies apart from moths. The clouded Yellow above is a typical
butterfly, while the Burnet shown here on the left is a diurnal moth.
Although butterflies form a rather homogeneous group, there are clearly recognisable subgroups.
The vernacular names of these subgroups often refer to the typical predominant color of many
members of these subgroups. So most 'Whites' are predominantly whitely colored, and many males
of 'Blues' are bluely colored. Although the fit between these vernacular names and reality is
not too strong, it is strong enough for field guides to be arranged according to these colors!
(For instance, Butterflies of Europe by Lafranchis is thusly organized.) Structural criteria
to delineate the various groups of butterflies concern the functionality of forelegs, wing venation
and the shape of the antenna's club.
In the systematic overview, you will find photographs of butterflies from different spots all
over Western Europe; in total some 140 species are represented, about 30% of all European species.
Also, I try to present an idea of the surroundings where the butterlies live, so I offer photographs
of landscapes and habitats (miniature landscapes) that I found the butterflies in. These photographs
are presented in the systematic overview, in the annotation of a particular photograph.
Scientific names are in accordance with Fauna Europaea.
I briefly describe some of the idiosyncracies of butterfly names in my
Short Note on Butterfly Names. In the much longer
Notes on the Naming Game I also explain
why names keep changing. These notes are written for a non-specialist audience.
I present information on various life history and behavioural aspects via the topical index.
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