Insects conquered the Earth long before we did and will remain here long after we’re gone. They outnumber us in the billions and are essential to many of the natural processes that keep us alive and that we take for granted. Yet, despite this, very few of us know much about the hidden world of insects. In this fascinating new book, entomologist and broadcaster George McGavin takes a deep dive to reveal the unknown truths about the most successful and enduring animal group the world has ever seen, and to show the unseen effects this vast population has on our planet, if only we care to look. McGavin explores not only the incredible traits that insects have evolved to possess, such as dragonflies that can fly across oceans without resting or beetles that lay their eggs exclusively in corpses, but also the vital lessons we have learnt from them, including how therapy using maggots can save lives and how bees can help grow rich tomato yields. The Hidden World reveals the wonderful complexity of our relationship with insects, how they have changed the course of our history and how, if we continue to learn from them, they could even be the key to our future and survival.
George McGavin, a renowned entomologist, is an honorary research associate at the Oxford University Museum of Natural History and the Department of Zoology of Oxford University. He has several insect species named in his honor. He lives in England.
This book is one where it is impossible for the author’s enthusiasm to rub off on you. That’s not too unusual when we are looking at books about nature, but because this is about insects, the under-appreciated but incredibly important beings of the natural world, it’s all the more impressive. The book is full of insights as well as quite basic information about ecosystem, and there is a fair bit of repetition about basic concepts. However, I am mindful that he’s writing to a general audience and nature enthusiasts first, and thus I am not squarely in his target audience. However, I think he does a good job of pitching to multiple audiences, and I still learned a fair bit. I listened to the audiobook and it comes with bonus content. I will say that the bonus content seems to be for people who can’t get enough of the content, as it makes the recording 14.5 hours long!! Even for a nature nerd like me, that’s a lot. Still, the core content offers an informative, wholesome, delightful read, and hopefully it will make more people appreciate everything insects do for us.
Absolutely brilliant and informative book which has some really interesting information, interviews with experts and fantastic story telling in it. It has changed how I see insects and also really hammered home how we need to look after all creatures on our planet. I couldn’t put it down, it was an absolutely wonderful read.
A very interesting book about insects and... how they sustain life and will shape our lives. Includes a lot of interesting knowledge about why insects are they way they are and how they work and the information combined with the enthusiasm of the author really grew on me.
“Once you start to read up about this ordinary little thing that you see in your bathroom you find out the most incredible things.”
“They are the most diverse and abundant group of animals that have ever lived. They made the world. They maintain the world. ”
“they also tend to overlook the importance of small creatures”
“insects conquered the planet long ago”
“Their total biomass is at least 10 times that of all humans and our livestock combined”
“We are newcomers on a planet made and maintained by insects.”
“The sum total of all vertebrate species – fish, birds, amphibians, reptiles, mammals, the whole beastly bestiary, from aardvarks to zebras and bats to blue whales – makes up a little under 3% of all species alive today”
“we still cannot answer one fundamental question – how many species are there on Earth?”
“it was recently claimed that 1 trillion species might currently live on Earth, with only one-thousandth of 1% described. This is due to the realisation that soil, sometimes dubbed ‘the poor man’s rainforest’, contains an incredibly diverse and understudied community of bacteria and other microorganisms.”
“sum of biological variation from the level of genes and species up to ecosystems”
“Some of the chemical building blocks of life, including organic molecules, may have arrived from space carried by comets and asteroids. So far, more than 140 biologically relevant molecules from those bodies have been identified.”
“the first photosynthetic organisms, the best known of which are the cyanobacteria”
“Very few multicellular organisms today are anaerobes, and those that are find themselves confined to deep-sea habitats, where they use hydrogen as an energy source”
“multicellular organisms can get much bigger,”
“The division of labour itself leads to more specialisation”
“multicellularity relies above all else on communication and cooperation between cells”
“Cancer is an example of what can happen when the strict regulation of cells breaks down and cells, once working for the common good, start behaving like independent agents looking out for themselves”
“bilaterally symmetrical along the longitudinal plane”
“pattern that evolution can endlessly tweak and refine”
“many species developed hard parts reinforced with calcium carbonate, perhaps in response to increased levels of predation. ”
“trackways and trace fossils showing parallel rows of marks made by legs, with a central line of broken marks perhaps created by the end of an abdomen”
“lightweight and waterproof exoskeleton which protects them and keeps them from drying up”
“how animals, particularly insects, know what to eat and when to eat it”
“fly maggots”
“insects have specific appetites for different nutrients”
“need protein because it contains nitrogen, an essential element when it comes to building and maintaining new tissues and reproducing”
“a dilution of protein in the human food supply – which is what’s happened over the last 50 years or so as a result of the incorporation of vast quantities of highly processed fats and carbohydrates in the form of ultra-processed foods – is what’s driving overconsumption of total energy, which leads to obesity”
“protein leverage hypothesis”
“Very seldom in the natural world have foods evolved for the purpose of being eaten. Generally, it’s the other way round: your foods try not to be eaten”
“Karl von Frisch with his work on bees or Niko Tinbergen with his work on wasps’ spatial location and how animals navigate and understand where they are in space”
“Treehoppers”
“capable of a degree of self-repair and, importantly, forms an exoskeleton, providing anchor points to which the internal musculature is attached”
“nothing we have manufactured thus far quite matches the versatility and effectiveness of an insect’s cuticle.”
“The smallest bacterial cell, at around 0.3 millionths of a millimetre, is 10 times smaller than the finest strand of spider silk”
“parasitic wasp that lay their eggs inside the eggs of other insects”
“half the size of some single-celled organisms, such as an amoeba”
“The atmosphere today comprises about 21% oxygen, but in the Carboniferous Period, partly as a result of the extensive forests growing at that time, oxygen made up as much as 35% of the atmosphere”
“Insects can occupy many more ecological niches than larger organisms can.”
“the nervous system is completely separated from the rest of the bodily fluids and can thus function efficiently at all times”
“If it were not for the insulating properties of the glial cells, electrical signals passing through the million or so neurons that make up an insect’s nervous system would become severely degraded”
“compound eyes. These eyes are made up of individual light-receptive units called facets, and there may be anything from one or two in some ants to more than 10,000 in dragonflies”
“A likely explanation of why zebras look the way they do is because it seems that blood-feeding flies don’t like landing on stripes”
“flowers, which have co-evolved with pollinators, often have distinctive markings called nectar guides, which are only visible to us if they are illuminated by ultraviolet light”
“responsive to vibrations and even the gentlest puff of wind”
“the conventional laws of aerodynamics that work well for aeroplanes and helicopters don’t work when it when it comes to describing how insects stay airborne”
“the wings of the very smallest insects are no more than thin struts fringed with slender hairs and move in a manner not seen in larger insects, allowing the insects to fly at speeds equal to those three times their size”
“how best to make miniature aerial vehicles for search and surveillance missions”
“the descendants of a single pair of house flies could, in a year, cover the surface of the Earth to a depth of 14 metres”
“insect numbers are controlled by lots of different factors, such as adverse weather, disease, predation and food availability”
“what makes Wytham Woods unique is that there have been more biologists observing, recording, measuring and experimenting within its boundaries than probably anywhere else on the surface of our planet”
“ Why was it so rare? Did it occur elsewhere in Europe and, in the UK, live right at the edge of the range of possible habitat that is suitable for its needs? What species preyed on it? Were there bacterial or fungal diseases that kept it rare?”
“the study of organisms, their relationships with other organisms and the physical environment”
“how each species lives and how they die, what they need and what they don’t need”
“Food chains depend on them. Insects are the world’s food. We depend on pollinating insects, especially bees, for perhaps as much as a third of the food we eat. As recyclers, flies and beetles devour carcasses, and clear prodigious quantities of dung from the surface of the planet every day.”
“ all the heaving, snorting herds of grazing ungulates are entirely ‘out-munched’, perhaps by a factor of 10 to 1, by billions of tiny mandibles”
“insects eat many times more animal flesh than all the vertebrate carnivores put together.”
“Ants alone are the major meat-eating species in any habitat”
“You can’t have more herbivores than there are plants for them to eat, nor can there be more carnivores than there is prey”
“the oldest profession’, then it must be taxonomy: the description, identification and classification of organisms”
“biomass, the total mass of biological material – plants, insects or birds”
“The energy plants trap by photosynthesis and convert into food is the start of many terrestrial food chains”
“Only 2% at most of the Sun’s energy is harnessed by plants and converted into food. When this stored energy is consumed by a herbivore, only about 10% of it is used to make herbivore biomass. The rest is used to power the herbivore’s metabolism and some is lost as heat”
“they are both the main consumers of plants and the most prolific carnivores on Earth”
“Without insects, it would be hard to see how complex ecosystems could ever have evolved.”
“What supports the pyramid of life on Earth”
“Soil may seem abundant, but it’s not. The average thickness of the Earth’s crust is somewhere between 15 and 20 kilometres, but this only accounts for less than 1% of the planet’s volume.”
“Soil anchors, supports and feeds plants, as well as regulates the flow and quality of fresh water. It is also rich in species and is a crucial store of carbon. ”
“Beginning with the relentless wearing down of mountains by wind and rain”
“It can take anything from 500 to 1,000 years to create 2.5 centimetres (1 inch) of topsoil”
“since the advent of agriculture, it has been steadily degraded and eroded”
“A teaspoonful of it may contain a billion or more bacterial cells, 200 metres of fungal threads and hundreds of tiny organisms from various different animal groups”
“Worldwide, the loss is between 25 and 36 billion tonnes every year. ”
“Intensive crop production leads to the loss of soil nutrients and the increasing reliance on fertilisers”
“Rather than relying on the wasteful and haphazard nature of wind pollination”
“The collaboration between flowering plants and pollinating insects is the most widespread and significant symbiosis on the planet today and, as a result, flowering plants now make up 90% of all plant species and more than three quarters of all insects depend on them”
“machair, the coastal grassy plains found on the west coast of Scotland and Ireland”
“the more species you have in a habitat – the more complex and diverse an ecosystem is – the more resilient it is”
“We are reliant on the species that help us along the way: the decomposers, the pest controllers, the pollinators”
“Four Pests Campaign in China during the Great Leap Forward that took place between 1958 and 1962”
“large parts of Britain’s landscape are completely man-made. The picture-postcard image of rural beauty is largely manufactured. Woodland has been felled, land has been drained, streams and rivers have been diverted and grasslands have been artificially fertilised to make better fodder for grazing animals”
“succession”
“The often bleak-looking and denuded Scottish Highlands would not look the way they do today if it were not for sheep and deer, not to mention the heather-burning that allows large numbers of imported birds to be reared simply for the ‘sport’ of shooting them”
“The lack of rabbits had a knock-on effect on rabbit predators such as weasels and stoats”
“different habitats and microhabitats available,”
“you will only know what these are by studying the specific requirements of the species you want to conserve”
“leaving dead wood lying around”
“If the land mechanism as a whole is good, then every part is good, whether we understand it or not”
“his long legs are used as a corral to protect the female from the attentions of other males until she lays her eggs.”
“the need to make sure that no other males come anywhere near the female until her eggs are laid is a common feature of insect sex and has resulted in the evolution of a whole range of mechanisms”
“Insect genitalia are important because differences in their structure are a sure-fire way of showing that species are different”
“The prophylactic misuse of veterinary drugs, especially antibiotics, is widespread, and is contributing to the steep rise in bacterial resistance to drugs.”
“the world’s cattle alone produce over 30 billion kilograms of dung every single day”
“their sex life involves a certain degree of violence and coercion”
“mole crickets are far more interesting because they are exceptional acoustic engineers. They construct elaborate burrows to make their songs more audible”
“early manufacturers of loudspeakers copied the exact shape of the crickets’ acoustic horns”
“males can turn their ‘ears’ off when they are calling so that their hearing will not be damaged”
“The loudest cicada calls have been recorded at 120 decibels, which is louder than a live rock concert and well above the human pain threshold”
“In most cases, it’s only the males that sing in order to advertise their presence and readiness to mate with the females”
“females will discriminate against smaller males using this method”
“female crickets are quite promiscuous and will mate with a large number of males”
“females are able to distinguish between males in good and poor condition by engaging in this strategy, because only males that are in good condition can actually produce the full 58 spermatophores in this timeframe.”
“the loser will remember the identity of the one who beat them and will avoid engaging them in direct confrontation again”
“At one point, the field cricket was limited to a population of roughly 100 individuals.”
“The queen may mate with a dozen or more drones, and it may take more than one flight before she has stored enough sperm in her spermatheca to last her a lifetime.”
“she will lay as many as a couple of thousand eggs every day for the next 4 years”
“insects seek to fine-tune the basic reproductive strategy to make it as effective as possible”
“if she is hungry, she will imitate the flashes of a female of the smaller firefly to lure the males to their death”
“giant water bugs. Here, unusually in the insect kingdom, it is the females who take on the job of courtship. They compete for available males, on to whose folded front wings they glue their eggs”
“The faster they breed, the quicker they can adapt to environmental changes, and the more they successfully reproduce, the better are their offspring’s chances of survival”
“ The larvae of the Human Bot Fly, as it is known, develop in the skin of a number of wild and domesticated animals”
“Myiasis is the technical term for the condition where the larvae of insects burrow into animals”
“parasitoids. That is, they lay their eggs on or in the tissues of a host animal, typically an insect or spider. The wasp eggs hatch and the larvae eat the host alive”
“The word ‘parasitoid’ is used to distinguish this lifestyle from that of a parasite, where killing the host is not really such a good idea.”
“These wasps, and many others like them that consume and kill their hosts, are a vital part of the natural processes that regulate insect populations. Without this control, the numbers of certain species would increase greatly – overwhelming host plants and upsetting the balance”
“The narrow waist makes the abdomen of wasps highly manoeuvrable and capable of getting to just about anywhere it can reach”
“as the parasitoid larva grows, it avoids eating anything that will seriously damage the caterpillar’s ability to feed and grow”
“Meanwhile, the wasp larva quietly feeds and grows inside, perhaps eating just fat tissue and fluids. But when it reaches a certain size and ‘knows’ the finishing line is in sight, it goes on a feeding frenzy.”
“The countryside around you may appear nice and peaceful, a tranquil idyll, but it is a biological battleground where just about anything goes and nobody is safe”
“Many plants give off airborne chemicals in response to being munched, and these chemicals are known to attract parasitoid wasps.”
“able to subtly alter the ratios of different compounds in the chemical mix in response to different sorts of herbivores, whether they be leaf-chewers such as white butterfly caterpillars, sap-suckers like aphids, or generalist grazers like slugs.”
“a full quarter of ‘creation’ exists to consume the rest of ‘creation’ alive.”
“The female sabre wasp uses her antennae to detect faint odours coming from the burrowing woodwasp larvae and, once satisfied that a particular spot is worth her while, she starts to probe the surface of the wood with her ovipositor”
“The cuticle of the ovipositor is also hardened by the addition of metal ions such as zinc and manganese.”
“the flies are specific to one ant species”
“After it hatches, the larva will move into the head, where it will initially feed on fluids. As the larva grows it will eventually consume all the juicy jaw muscles and the brain”
“members of a special caste of workers, called minims, are much smaller than the major workers. They sit on top of the leaf loads, keep watch for flies above and dislodge any that do land”
“Insect excrement, known as frass, is often used by parasitoids as a cue – the insect that produced it might be close by”
“bees also face a great number of natural enemies. Attacked by anything from viruses, bacteria and fungi to spiders, hornets and birds”
“The Black Oil Beetle”
“The hatching of her eggs is timed to coincide with the appearance of certain solitary bees.”
“All of this behaviour is, to a large degree, programmed”
“the elegance and complexity of their lives.”
“The fly larvae will start by eating the bee’s bodily fluids and fat tissues before going on to eat her ovaries. The bee is alive even up to the point when the entire contents of its abdomen have been consumed”
“This stealthy bit of mind control is highly advantageous to the fly, because it now has a safe place in which it can spend the cold months of winter”
“nature is not cold and unfeeling. It is merely functional – and parasites and parasitoids are a part of the ecological machinery”
“With the plethora of parasites that exist specifically to gorge themselves on live insects, I’m not sure I’d like to be any insect at all”
“life on Earth depends on death and decomposition. Living things are made from the remains of dead things”
“Every single atom that makes up you and me has been used before”
“You will die but the carbon will not – its career does not end with you. It will return to the soil, and there a plant may take it up again in time, sending it once more on a cycle of plant and animal life”
“At an atomic level we are immortal”
“carrion flies, bluebottles and green-bottles, these flies are pretty much everywhere most of the time – waiting to detect the faintest whiff of something rancid or rotten that will tell them that a good place to lay their eggs is not far away”
“BBC programme called After Life: The Strange Science of Decay”
“molecules associated with decomposition – appropriately named organic compounds such as putrescine and cadaverine, resulting from the breakdown of amino acids – have a particular property: they are highly electrically charged.”
“ reason for this communal feeding behaviour. A single maggot on its own would not do nearly as well as it would being part of a larger group, in which all of their digestive enzymes can be pooled”
“ A rat might provide enough sustenance to produce 4,000 blow flies. It has been estimated that fly larvae can consume 60% of a human corpse in a week”
The Hidden World - How Insects Sustain Life on Earth Today and Will Shape Our Lives Tomorrow
by
George McGavin
We rule this world and this earth belongs to us... or so we would like to believe.
Learning about insects comes with a lesson in humility. They have been here long before we turned up and will in all likelihood outlive humanity by a long shot.
Obviously there are a great many bugs out there that do not directly benefit us or outright do us harm. But that's simply because the world doesn't revolve around us and not everything is meant to serve us and that's okay.
But it doesn't take away from the fact that insects are fascinating creatures that come in all sorts of shapes and sizes, each species playing a crucial role in maintaining the equilibrium that forms the very basis of our survival. One thing is abundantly clear: No bugs means no humans, though our extinction will probably not faze insects all that much.
Much of the phobia around insects probably stems from not knowing enough about them. Many species are hugely beneficial to us by pollinating our plants, recycling dead organic matter, and serving us in science and medicine. And their biology is just absolutely remarkable.
McGavin's enthusiasm is contagious and I have now a newfound appreciation for this hidden world.
British entomologist Dr. George McGavin passionately expresses his fascination with insects and his love for the natural world. He takes the time to introduce us to several species of insects, describes everything from their feeding to their mating habits, and helps the reader understand how they fit into their ecosystem. However, it's not all roses—McGavin's despondency for the future of the natural world is very clear. He is gravely concerned about the destruction of natural habitats and the resulting loss of biodiversity (as he, and all of us, should be).
The book is written in a breezy, Sunday-afternoon-educational-television-program tone. There honestly isn't a ton here that would be new or surprising to anyone who regularly reads books/watches documentaries on the subject of the natural world. That isn't to say I did not learn anything, and there are plenty of interesting facts in here. But one of the best parts of this book is in the interviews that McGavin conducts for the audiobook. He has a casual conversation with naturalists, biologists, and entomologists about their particular areas of study and the broader global crisis. The knowledge and passion of these interviewees is readily apparent and make for some great listening. They certainly make this a worthy book to pick up and give a listen to.
I was looking for a book about insect life that was readable, partly because I am a fly fisherman and really need to boost my knowledge of entomology. This briskly written book has partly achieved that, and the author- who is not a fly fisherman - even co-wrote a book with an angler to provide insight into the ways of insects. I learned a lot from this book but the narrative is annoyingly broken by the author's interviews with various experts. Their views I feel could have been woven much more seamlessly into the narrative. It is also a bit lazy to fill space in a book with the transcriptions of extended interviews - the editors who did not push back on this daft idea need to have this error reflected in their annual performance reviews. Still, a nice overview of the astonishing evolution of insects and their crucial role in the global web of life ...
McGavin shares with the reader his professional and personal fascinating with this largest class of organisms on Earth. He explores their extraordinary lives, the services they fulfill for the planet, their particular contributions to the benefits of humanity and their tentative future in an earth changed by human actions. The work includes several small interviews with fellow scientist and science communicators that emphasize how much humanity is still learning from insects and the increasing awareness of the dangers of their absence. An easy-to-read introduction to the fascinating world of insects.
As a lover of insects I really enjoyed this book. I strongly recommend the audiobook which includes interviews with lots of experts. As far as insect books go this is one of the more optimistic ones I've read. The author acknowledges we are causing a huge mass extinction, but it also points out that no matter how badly we destroy the Earth some form of Insect is almost guaranteed to outlive us. The sections on micronutrient appetites and different reproductive strategies were especially informative.
A brilliant introduction to how insects have become the most successful lifeforms on earth, concluding with forecast that they will not only be present on earth long after humans have gone, but because of their amazing diversity and anatomy, insects would be better colonisers of future planets than humans ever could be. This very personal insight, including entertaining interviews with famous scientists, should be on everyone’s reading list.
3 Stars - it was a decent read but I have read better insect books. I felt that there was a lot of pieces of information that stopped too soon. I needed more depth. Also there weren't any diagrams or pictures or photos in this book which I think was a big mistake. Overall it was decent and interesting at times but didnt have the detail I was hoping for.
Interesting and mostly good + accurate points. There’s some glossing over facts and stretching of reality for dramatic effect but that’s mostly to be expected with books such as these. However it’s still overall not a very profound book.
I enjoyed this book. It is filled with facts and anecdotes about insects. The writing is informal, engaging, and easy to read. There are a handful of interviews throughout which I enjoyed less than the sections where the author talks about his passion for natural world.
I listened to this before bed, so the random loud insect noises were... not exactly restful. Also, if you're going to put in a trigger warning about insects that burrow into your skin, perhaps do it before you tell the (extremely graphic) story and not afterwards???