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The Beetle Kingdom - a brief introduction for children and families by Benedict John Pollard  Introduction It is a widely accepted notion amongst Natural Historians that there are more species of beetle on Earth than any other group of organisms. Estimates vary from 400,000 to as many as over 2 million different species, with vast numbers of species yet to be discovered, especially in the beautiful humid tropics. Where to find beetles? Beetles have an amazing diversity of habits and habitats and are an essential part of the interconnectedness of life. They can be found on the ground, on grasses, shrubs, trees, flowers, inside stems, under bark, under logs, in puddles, in birds’ nests, ants’ nests, badger setts, rabbit warrens, in grass tussocks, fungi, rotting wood, amongst algae, under driftwood on the sea shore. Some are active in the daytime, and others emerge at night. Broader habitats include meadows, pastureland, forest, lakes, ponds, streams, on sand dunes, rock-pools, cliff ledges, saltmarshes, reedbeds, and even one can find many interesting species in old industrial wastelands. One can even start looking simply, by just inspecting leaves as you walk by. This is how I started, just a few years ago. The image below is of the Alder Leaf Beetle which was thought to be extinct in Britain, after being recorded in the Victorian era. In just the last couple of years it’s population has suddenly undergone an ‘explosion’ and it is being reported all over the country in Britain, which goes to show that there is so much to learn, as nobody is quite sure why it has made such a remarkable ‘comeback’.  What do they do? Pollinators: whilst the bees currently seem to get all the ‘glory’ in the popular press for pollinating our crops and fruits, in actual fact, many species of beetles also act as pollinators of a wide variety of flowers. Recyclers: many species help to perform a crucial ecological role in accelerating the breakdown and decomposition of dead plants or animals, often making their homes in the old dead wood of trees, and are a kind of valuable natural ‘compost maker’ in that regard. These are called saproxylic beetles. The dung beetles recycle animal waste and act as key species in nutrient cycling in the soil. Symbiosis: making friends with other forms of life. Ambrosia beetles have an amazing life story: living in a nutritional partnership with ambrosia fungi. They have a specialised structure called a ‘mycangium’ which is a pocket-like structure that they use to store and transport fungal spores. When they land on a new tree, they create tunnels under the bark to live in, and they then spread the spores inside, creating a ‘magical’ fungal garden which they nurture and tend, to provide themselves with food. A sense of scale One of the wonders of studying beetles is that one can reorient one’s perspective. There is a whole other world waiting to be discovered, one of miniature landscapes, where everything is reduced in size, and yet life continues on, much as for any other animal. The picture below gives you an idea of what I mean. It is a photo of a species in the Carabidae, the Ground Beetle family, scurrying about amongst the moss on a fallen oak limb. If you look carefully you will see some interesting looking things on it’s pronotum (back). Some people think these are some sort of parasite, and cause the beetle harm, but this is not the case. They are called Phoretic mites, and are just hitch-hikers, utilising the beetle as a means to get from one place to another, presumably over distances longer than they would normally be able to cover alone, and in a way that is safer for them. I suppose you could say they are using a sort of taxi service, and that the beetle is quite generous to its little friends. To give you a sense of scale, the beetle is only about 2cm long.  Naming a beetle: how are scientific names created? All organisms are nowadays usually identified using a simple system for classifying species, called the binomial nomenclature. This literally means a ‘two-named’ [bi-nomial] ‘system of naming’ [nomen-clature] which was developed and adopted by a Swedish naturalist called Carl Linnaeus, in the late 1700s. This allows people to refer to any one species in the same way, even if they come from very different parts of the world, and have completely different languages. For example, to a scientist working in a zoo in Singapore or Australia , or a ranger working on a conservation project in west-central Africa, humans are known as Homo sapiens, and Gorillas are broadly known as Gorilla gorilla. A fisherman in America or England or Belarus knows that the strikingly handsome fish that we know by the name ‘Pike’, is scientifically referred to as Esox lucius. This all helps us to develop our scientific understanding of life forms and processes. What is a beetle? Beetles are a type of insect, meaning they have specific characteristics such as having six legs, antennae, and an ‘exoskeleton’. Exoskeleton means that the protective hard parts are on the outside of the body, unlike in people, other mammals or fish, for example, which obviously have their skeleton on the inside (‘endoskeletons’). Beetles belong to an ‘Order’ of insects known as Coleoptera, which means ‘Sheath wings’ referring to the often colourful hardened outer wing cases, which protect the more typical wings that are usually folded underneath. The outer wing-cases are known as elytra (pl., singular elytron), and meet in the middle along a neat suture/line. They are distinguished from other insect Orders by having two true wings, but unlike flies (Diptera), which also have two wings, flies don’t have such protective wing-cases. Rarely one can find wingless beetles, and there are some groups of beetles that do have wings but very rarely fly. Bees, wasps and flying ants (Hymenoptera) are different in that they have four wings. There are a number of other different groups of insects which have their own characteristics which can be studied and used to distinguish one from another. These include, among others:
As you can see, there is an amazing range of different insects, and much to learn. Much has yet to be discovered, and species new to the UK are still being discovered every year. The number of beetle species known in Britain currently stands at just over 4,100 species. For comparison, there are about three times as many beetles as there are plants native to the UK. More information can be found here: https://www.amentsoc.org/insects/fact-files/orders/ Beetle families, some example: Within the beetle ‘kingdom’, there are then many beetle families (over 110 families in the UK), which represent a series of smaller units that can be grouped together. This helps us to understand and identify the beetles better and reflects groups with common characteristics, so we can distinguish them more easily from amongst the huge diversity of species Here we take a brief look at some of the commoner families that you might encounter on your walks in the woods, or adventures out in nature. A family of beetles will generally be scientifically known by a single word, ending in the two letters ‘-ae’, such as Carabidae or Coccinellidae. Here are some example of beetle families you might find on your expeditions outside. Soldier Beetles – Cantharidae Ground Beetles – Carabidae Longhorn Beetles - Cerambycidae Leaf Beetles – Chrysomelidae Ladybirds – Coccinellidae Weevils – Curculionidae Pleasing Fungus Beetles – Erotylidae Clown Beetles – Histeridae Glow Worms – Lampyridae Mould Beetles – Latridiidae Stag Beetles – Lucanidae Tumbling Flower Beetles – Mordellidae Hairy Fungus Beetles – Mycetophagidae Pollen Beetles – Nitidulidae Dung Beetles – Scarabaeidae Rove Beetles – Staphylinidae Now we start you off on your journey of discovery, by looking at some of the families of beetles, and we can start with some of the ‘saproxylic’ beetles, from the ancient Greek language, literally means ‘rotten’ [sapro-] + ‘wood’ [xylic], and these do such an amazing job of starting the process of turning fallen or dead wood into a kind of ‘compost’ and soil, eventually. What wonderful little busy-bodies they are, quietly going about their essential business.
Beetles and trees are often best of friends It is a known fact that a single ancient English oak tree, can be home to many rare beetle species, and can even have provided many generations of a single ancestral line of a particular beetle species over hundreds of years. This tells us that every single old tree has tremendous value in this way, and helps foster in us a deeper appreciation of all the small little beings that live inside or on the trees, usually unseen, and call them their home. The beetle relies on the tree and the tree also welcomes the beetle. The species of Ampedus illustrated above, live in this way, and are very rarely seen. As you will note, Ampedus nigerrimus, has a code after its name: 6 NBN. This means it is very rare indeed, and has only been found in 6 places in the UK, according to the National Biodiversity Gateway, which is a useful resource for anyone studying wildlife in the UK. https://nbn.org.uk/ Another very useful website in the UK is ‘i-record’ https://www.brc.ac.uk/irecord/ Wonderful old oaks It is interesting to note that 99% of ancient oaks, for example, are hollow. This is a natural part of their life cycle, and in fact a hollow tree is often stronger than a solid tree, a bit like how hollow bamboo or metal scaffolding poles are stronger than similar solid structures. In fact, in the tropics, bamboo is often used as a scaffolding pole when building a house, on account of its strength. When these ancient trees are hollow, it helps them to better withstand the strong winds that blow, and in the case of oak trees can enable them to live for many hundreds of years. It is a saying in England that an oak tree grows for 300 years (youth), lives for 300 years (maturity) and then declines for 300 years (senescence, or old age). The saproxylic beetles that live in them eat the old dead rotten wood inside, and therefore actually enable the tree to survive for longer, to a grand old age. They do this by helping to hollow out the middle of the tree over many many generations, by eating the wood that fungi start to decompose. What a wonderful partnership – one of the many marvels of the natural world! Why do I like beetles? I only really started studying beetles seriously in 2018, and since buying a microscope in February 2020, my understanding of these little creatures has accelerated enormously. I still wonder at their extraordinary beauty, and the fascinating diversity of shape, size, colour and character. It seems to me that beetles are often overlooked because we simply can’t easily see them. So they are forgotten. Sometimes they are less than one millimetre in length, and if they are still, they just resemble a small bit of dirt. So when you see a piece of ‘dirt’ starting to walk, you know you need to look a little bit closer and with a bit more care. Every beetle has its place, its life, and its own little world, which operates at a different to scale to us. So who is to say that a beetle is any less important than any other creature? They each make their own little homes, they drink water when they’re thirsty, and eat when they’re hungry, they have characteristic ways of moving, some slow, some fast, some jittery, some smooth. All around us, all the time, they are busy naturally eating wood, brushing pollen from one flower to another, breaking down the things that perhaps people wouldn’t like to: dung, rotten wood and smelly fungi. They make soil, aerate, pollinate. I sometimes wonder if they sing, or dance or dream. In truth, we know very little about beetles, but it surely behooves us to look after them and care for them and their little worlds. “A beetle may or may not be inferior to man – the matter awaits demonstration; but if he were inferior to man by ten thousand fathoms, the fact remains that there is probably a beetle view of things of which a man is entirely ignorant. If he wishes to conceive that point of view, he will scarcely reach it by persistently revelling in the fact that he is not a beetle.” G.K. Chesterton. The Defendant (1901) Great Find! – Laemophloeus monilis – the story of it’s discovery As I write this article, I am still basking in the glow of an exciting discovery made just last night, Sunday 11th October 2020. I am taking part in a biodiversity survey of an ancient oak woodland near where I live. There are over 40 volunteers taking part, mostly people who are specialists in their field of study. From time to time I have permission from the estate owner to do some beetle surveying. Yesterday I arrived at the woods at around 2:45pm, and slightly berated myself for not arriving there earlier to make use of the sunlight. For a few hours I didn’t really find anything of note, which meant I felt a little bit despondent. I had carefully packed all of my equipment, including spare batteries for my head torch, in case I decided to do some searching at dusk. I made my way down to the old timber yard where the estate take all the big trees that have blown down or fallen over or perhaps are a little bit dangerous to be near paths where the public walk. I spent quite a while here, lifting up some of the bark on the logs and finding all sorts of interesting looking species there. As I can’t always identify a beetle straight away, I will pop them in a small container, and take them home where I can look at them under the microscope. As dusk approached I became quite annoyed as it seems I had forgotten my head torch, so I was on the verge of heading home when two ladies walked past, and then a few minutes later reappeared and asked for help, as they were lost. After a few minutes of explanation and a phone call to the security guard I managed to explain to them how they could find their way back out of the estate. After our little meeting was all concluded, the dark had almost arrived, and I decided to see if my phone had a good enough torch on it to continue surveying. To my amazement it did and is very powerful and it does not seem to affect the battery life very much. So I carried on. There are probably over 300 large logs in the timber yard, from lots of different species of tree, and they had lain there for differing amounts of time. Some of them are clearly from old trees, as they are over 1m in diameter. So I carried on for two hours after dark, enjoying the calls of the owls around me, checking and then rechecking the ends of every log, and there were all sorts of interesting things that emerged. I eventually headed home, and quickly had a look under the microscope to see what I had found, as it’s quite difficult to differentiate the species just using one’s eyes, because the largest one I found was only about 4mm long. After some initial research, I saw a handsome little beastie, which I did not recognise at all, not even able to attribute it to a beetle family. Once I had eaten dinner, I continued on, and realised it was a species known scientifically as Laemophloeus monilis. After a bit more research and a few emails and discussions with other specialists on-line, it turns out that it is only known in Britain from about five places. One very experienced beetler told me he has been looking for it for almost 60 years, with no luck. I couldn’t believe my good fortune. It belongs to a family known as the Lined Flat Bark Beetles: Laemophloidae See below for a photograph of the author’s specimen, and a reference image courtesy Lech Borowiec.  Another favourite Beetle – Opilo mollis On one of my first beetle surveys at night, in early summer 2020, I went out into the woods with a head torch, and foud this lovely little beetle slowly walking across the tree trunk of a very old oak tree. It ambled gently along, and didn’t seem too bothered by the bright light. It made me wonder what does it get up to at night? Does it sleep during the day? Where does it sleep? Has it made itself a nice little nest somewhere, a cosy warm little snug inside the old tree bark? I wonder how long it lives for? A year, 2 years, 5 years? What does it do in winter when it’s cold, does it hibernate? I wonder how its colour patterns are helpul? Does it have friends and allies, and does it need to be careful of owls? And that’s when I realise there is a whole magical Kingdom of Beetles all around us, everywhere, and we know so little of these little creatures, and their wonder. Perhaps it’s time they were treated more kindly and thoughtfully and with the sense of reverence that the natural world can really bring out from within us, as we marvel at its majesty.  Suggested family activities
If it weren’t for the beetles and the fungi and bacteria, and how they decompose wood, we would probably have scattered piles of dead trees miles high, all over the place! Imagine that! There is still much to learn and much to understand about how beetles help keep our environment and microclimate stable and rich and thriving. We really encourage families to take a further look, go out into nature and enjoy meeting these little marvels. It’s lovely to explore nature and to go on your own beetle discovery walk. A few suggestions of activities and questions for you to contemplate
Enjoy your adventures!
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Welcome to the Learning Corner!Eenie introduces us to some of his insect and animal friends, to different places, to the ways of the weather and to the wonderful world. Eenie also shows us how to feel happy and healthy! READ MORE >
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The AuthorDr Linda Spedding creates this charming world of Eenie, the sparkly snail who enjoys wonderful adventures, sights and sounds - despite his very small stature- in a world where right values are illustrated and rhymed as memorable guides for young children. |
