Often regarded as a symbol of good luck, ladybirds are more than just cute. They are familiar insects, but they are also formidable predators.
They prey mainly on aphids and other plant pests. As such, they play an important role in natural pest control, which is highly valued in agriculture and horticulture.
To give you an idea of how much of an impact this has, one ladybird can eat up to 5,000 aphids in its lifetime. It is of such ecological importance that just looking at the numbers you immediately realise…
I may have caught ladybirds as a child, as did I, and some of you may have had a mystery fluid poured on your fingers. As a defence mechanism against predators, ladybirds produce a foul-smelling yellowish fluid from their leg joints when they sense danger.
This is a phenomenon known as ‘reflex haemorrhage’ and, together with its bright colours, is an effective deterrent to potential threats.
Ladybirds do not have the same round shape from childhood. It undergoes a transformation from egg to larva, pupa and adult. Unlike the smooth, button-like adult, the larva looks like a short caterpillar, which many people may find unpleasant.
Although not uncommon in insects, they can reproduce by a process called monogenesis, in which the eggs grow without fertilisation.
Size differences are also interesting. The smallest species of ladybirds are only 1 mm, whereas the largest species are over 1 cm. The largest is just over 1 cm, so it may not seem like much of a difference, but there is a tenfold difference between the smallest and the largest.
The larger ladybird has more impact, and I wondered whether I should put up a video of it too, but I thought some people might find it a bit creepy, so I decided not to, although I’m sorry to the ladybird. The larger ladybird looks more like a normal insect than a ladybird…
Their sense of taste and smell is thought to be located in their antennae.
They actually hibernate like bears. During overwintering, ladybirds congregate in large numbers in suitable warm places, such as tree crevices, grass roots and house eaves, and emerge when warmer weather returns.
Certain species, such as the colourful Asian ladybird beetle, invade houses in large numbers and have become nuisance pests in some areas.
Although they are considered relatively attractive creatures among insects, they also have a dark side. They engage in cannibalistic behaviour when food sources are scarce.
Other survival strategies include the brainy strategy of ‘playing dead’, in which some species drop to the ground and remain motionless when threatened.
Ladybirds, which have delicate membranous wings that fold neatly under colourful, hard wing cases called elytra, can fly at speeds of up to 15 mph (15 km/h).
In the genre of biomimicry, which applies the structure and movement of living organisms to engineering and other applications, ladybird flight has been studied with great interest.
In Christianity, it is associated with the Virgin Mary and thought to bring blessings and good luck.
On the other hand, it is also often associated with love and good luck in Asian cultures: in the popular 2010s Japanese anime Jojo’s Bizarre Adventure, the main character, an Italian, wears a ladybird brooch as a symbol of life. Basically, it could be said to be a blessed insect with a good image everywhere.
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