Nature is brutal

Nature is brutal

In nature there is no regulation. The environment can be brutal and unforgiving. If a creature can do something to another that will give it an advantage, it will be done.

Starvation, disease, predation, targeting the young, targeting eggs, being paralysed and eaten alive. What awfully violent and painful things. But the rest of the natural world has just evolved around it.

Predators appear that will prey on the predators. Animals have babies only at a certain time of the year to maximise their chances of survival. Prey animals cooperate, warn each other, and shun and drive off predators.

But taking resources, which may include life, from another creature is a fundamental aspect of nature. The only primary producers are plants and bacteria.

Bounds of shelter, food, predation, and disease

What's the size of the population? Are they straining their resources? They share their living environment with their resources, so they can easily feel it.

What happens every time an organism has an adaption that  makes it 'too successful', where it multiplies out of control? It fills the environment with its descendants, who are overwhelmed by either their consumption or by their own waste, and they must adapt or die.

Most species probably should be subject to the bounds of abundance of food, and/or predation.

Scarce food and no predation keeps a species in check.

Scarce food and predation sends a species extinct.

Abundant food and predation keeps a species in check.

Abundant food and no predation turns a species into a pest.

Famine and predation are nature's answer to population explosions caused by the tragedy of the commons.

We are in the fourth line: Abundant food and no predation, and we have become a pest on the planet.

We've worked out how to convert the natural world into food, and with no predators our population growth is uncontrolled. So we expand to fit the available 'space', pushing nature to the fringes.

See nature reservations.

Tropic cascades

It's when predators suppress their prey, so the prey can't eat as much. A cascade of effects flows down the food web.

Reddit community, TIL that reintroducing wolves to Yellowstone...

Reintroducing wolves to Yellowstone changed the entire geography of the park: as elk were displaced, saplings that would have been eaten by elk were spared, riverbank erosion was brought under control, and streams and rivers shifted their courses.

Wikipedia, Trophic cascade

Trophic cascades occur when predators in a food web suppress the abundance and/or alter traits (e.g., behavior) of their prey, thereby releasing the next lower trophic level from predation (or herbivory if the intermediate trophic level is an herbivore). For example, if the abundance of large piscivorous fish is increased in a lake, the abundance of their prey, zooplanktivorous fish, should decrease, large zooplankton abundance should increase, and phytoplankton biomass should decrease. This theory has stimulated new research in many areas of ecology. Trophic cascades may also be important for understanding the effects of removing top predators from food webs, as humans have done in many places through hunting and fishing activities.

A Top Down Cascade is a trophic cascade where the food chain or food web is disrupted by the removal of a top predator, or a third or fourth level consumer. On the other hand, a bottom up cascade occurs when a primary producer, or primary consumer is removed, and there is a diminishment of population size through the community. An example could include Paine's study from the University of Washington, where he removed several species in different plots along the North-Western United States coast line, and realized that Pisaster, a common starfish, when removed, created a top-down cascade which involved a surge in barnacle and mussel population, but a decrease in the populations of chitons, limpets, and whelks. This led to the conclusion that Pisaster was a keystone species in that food web.


Animals will kill species that compete with them, especially their young.


If there are grazers, there are hunters. And the hunters chase the prey or lure the prey.

It would be such an awful experience to be eaten by carnivores. Have a look at this YouTube video, Puma eats sloth. So sad. So unfair:

Scavengers are never far away.

Wikipedia, Trophic level

The¬†trophic level¬†of an¬†organism¬†is the position it occupies in a¬†food chain. The word trophic derives from the¬†Greek¬†ŌĄŌĀőŅŌÜőģ (trophńď) referring to food or feeding. A food chain represents a succession of organisms that eat another organism and are, in turn, eaten themselves. The number of steps an organism is from the start of the chain is a measure of its trophic level. Food chains start at trophic level 1 with¬†primary producers¬†such as plants, move to¬†herbivores¬†at level 2,¬†predators¬†at level 3 and typically finish with¬†carnivores¬†or¬†apex predators¬†at level 4 or 5. The path along the chain can form either a one-way flow, or a food "web." Ecological communities with higher biodiversity form more complex trophic paths.

The three basic ways organisms get food are as producers, consumers and decomposers.

Producers (autotrophs) are typically plants or algae. Plants and algae do not usually eat other organisms, but pull nutrients from the soil or the ocean and manufacture their own food using photosynthesis. For this reason, they are called primary producers. In this way, it is energy from the sun that usually powers the base of the food chain.( An exception occurs in deep-sea [hydrothermal ecosystems, where there is no sunlight. Here primary producers manufacture food through a process called chemosynthesis.(

Consumers (heterotrophs) are animals which cannot manufacture their own food and need to consume other organisms. Animals that eat primary producers (like plants) are called herbivores. Animals that eat other animals are called carnivores, and animals that eat both plant and other animals are called omnivores.

Decomposers (detritivores) break down dead plant and animal material and wastes and release it again as energy and nutrients into the ecosystem for recycling. Decomposers, such as bacteria and fungi (mushrooms), feed on waste and dead matter, converting it into inorganic chemicals that can be recycled as mineral nutrients for plants to use again.

Trophic levels can be represented by numbers, starting at level 1 with plants. Further trophic levels are numbered subsequently according to how far the organism is along the food chain.

Level 1: Plants and algae make their own food and are called primary producers.

Level 2: Herbivores eat plants and are called primary consumers.

Level 3: Carnivores which eat herbivores are called secondary consumers.

Level 4: Carnivores which eat other carnivores are called tertiary consumers.

Level 5: Apex predators which have no predators are at the top of the food chain.

Second trophic level

Rabbits eat plants at the first trophic level, so they are primary consumers.

Foxes eat rabbits at the second trophic level, so they are secondary consumers.

Golden eagles eat foxes at the third trophic level, so they are tertiary consumers.

The fungi on this tree feed on dead matter, converting it back to nutrients that primary producers can use.

In real world ecosystems, there is more than one food chain for most organisms, since most organisms eat more than one kind of food or are eaten by more than one type of predator. A diagram which sets out the intricate network of intersecting and overlapping food chains for an ecosystem is called its food web.( Decomposers are often left off food webs, but if included, they mark the end of a food chain.( Thus food chains start with primary producers and end with decay and decomposers. Since decomposers recycle nutrients, leaving them so they can be reused by primary producers, they are sometimes regarded as occupying their own trophic level.(

Biomass transfer efficiency


An energy pyramid illustrates how much energy is needed as it flows upwards to support the next trophic level. This diagram is not to scale, because only about 10 % of the energy transferred between each trophic level is converted to biomass.

Generally, each trophic level relates to the one below it by absorbing some of the energy it consumes, and in this way can be regarded as resting on, or supported by the next lower trophic level. Food chains can be diagrammed to illustrate the amount of energy that moves from one feeding level to the next in a food chain. This is called an energy pyramid. The energy transferred between levels can also be thought of as approximating to a transfer in biomass, so energy pyramids can also be viewed as biomass pyramids, picturing the amount of biomass that results at higher levels from biomass consumed at lower levels.

The efficiency with which energy or biomass is transferred from one trophic level to the next is called the ecological efficiency. Consumers at each level convert on average only about 10% of the chemical energy in their food to their own organic tissue. For this reason, food chains rarely extend for more than 5 or 6 levels. At the lowest trophic level (the bottom of the food chain), plants convert about 1% of the sunlight they receive into chemical energy. It follows from this that the total energy originally present in the incident sunlight that is finally embodied in a tertiary consumer is about 0.001%

Food webs largely define ecosystems, and the trophic levels define the position of organisms within the webs. But these trophic levels are not always simple integers, because organisms often feed at more than one trophic level.( For example, some carnivores also eat plants, and some plants are carnivores. A large carnivore may eat both smaller carnivores and herbivores; the bobcat eats rabbits, but the mountain lion eats both bobcats and rabbits. Animals can also eat each other; the bullfrog eats crayfish and crayfish eat young bullfrogs. The feeding habits of a juvenile animal, and consequently its trophic level, can change as it grows up.

Wikipedia, Prey drive

Prey drive** is the instinctive inclination of a carnivore to find, pursue and capture prey.

In all predators the prey drive follows an inevitable sequence: Search (orient, eye); Stalk, chase; Bite (grab-bite, kill-bite); dissect, consume.( In wolves, the prey drive is complete and balanced since it utilises the whole range from search to kill and finally consumes the prey in order to survive.(

In different breeds of dog certain of these five steps have been amplified or reduced by human-controlled selective breeding for various purposes. The "search" aspect of the prey drive, for example, is most valuable in detection dogs such as bloodhounds and beagles. The "eye-stalk" is a strong component of the behaviors used by herding dogs, who find herding its own reward. The "chase" is seen most clearly in racing dogs such as Greyhounds and Lurchers, while the "grab-bite" and "kill-bite" are valuable in the training of terriers.

In many breeds of dog, prey drive is so strong that the chance to satisfy the drive is its own reward, and extrinsic reinforcers are not required to compel the dog to perform the behaviour.

The void of the tiger


Save for the movements of the dog and the men, the forest has gone absolutely still; even the crows have withdrawn, waiting for this latest disturbance to pass. And so, it seems, has the tiger. Then, there is a sound: a brief, rushing exhale ‚ÄĒ the kind one would use to extinguish a candle. But there is something different about the volume of air being moved, and the force behind it ‚ÄĒ something bigger and deeper: this is not a human sound. At the same moment, perhaps ten yards ahead, the tip of a low fir branch spontaneously sheds its load of snow. The flakes powder down to the forest floor; the men freeze in mid-breath and, once again, all is still.


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Widowed animals

When an animal goes missing, many will try to find their missing mate. Many species are paired for life and it must be devastating.


Robert Bakker, Reddit AMA

Neither of these internet dino-tropes are accurate. Let me boil this down and not duplicate what Dr. Bakker stated:

Tyrannosaurus rex as a pure predator or an absolute scavenger is a false dichotomy. T. rex was -- like all apex carnivores -- an opportunistic carnivore. Protein is derived from the most accessible sources alive or dead. Lions do both. Hyaenas, too. All terrestrial meat-eaters are dual-mode feeders. The energy budget of land-based carnivores does not allow vulturine specialization.

It turns out that very few animals are pure scavengers like Turkey Vultures. These wonderful birds use little energy while riding thermals to seek a meal of roadkilled raccoon. Rex would use more energy (at scale) walking a hundred yards than a Turkey Vulture would use in an afternoon gliding on thermals.

Spino and Rex would have to travel through time and find accommodating transportation to even meet once. The reason this trope exists is, of course, due to the third Jurassic Park movie. The fight is simply not based in science - it is a plot device to introduce a bigger, scarier monster.

Hunting in pairs or more is better.

Hunting alone inevitably means you'll have to scavenge a little.

Assessing other animals

Robert Bakker, Raptor Red

A deep coughing roar announces the arrival of seven adult gastons. The baby coughs a reply. The male raptor studies the gastons as they advance. Short legs - very slow is his analysis. He's learned that the higher the body and the longer the shins and ankles, the faster the dinosaur. He can outrun nearly all his dinosaurian neighbors except for the ostrich dinos, small-headed omnivores with exceedingly elongated lower legs.

Then strike at the right opportunity, when the target is distracted.

Confident prey is suspicious.

Robert Bakker, Raptor Red, p203

  • It is a very windy day when the raptor pack meets the whip-tail brontosaur. Whenever the dark clots of clouds block the solar heat, the air becomes chilly and inhospitable. But mostly the air is clear and bright, and as long as they stay in the sun, the raptor sisters feel comfortable. The raptors see the whip-tail from two miles away---a dark mass moving alone in a mountain meadow. They try to sniff out some target data‚ÄĒWho is this potential prey? Is it too strong for an attack? Is it injured? The scent that wafts up from the whip-tail makes Raptor Red pause. It is like Astrodon scent‚ÄĒbut, on the other hand, it isn't. Raptor Red knows only one kind of brontosaurian‚ÄĒAstrodon itself‚ÄĒand she knows how to at When Raptor Red sees the whip-tail up close through the shrubs, the big dino is staring right back at her. Rap-tor Red doesn't like this at all. It's a universal rule: Predators of all ages are naturally suspicious of prey who don't appear to be scared. Self-confident prey are often those who have extra skill and strength in defense. Clearly the whip-tail is not rattled by the prospect of battling two Utahraptors. It sees Raptor Red's sister and swivels its head back and forth, keeping track of both raptors. The whip-tail moves deliberately out away from the treeline, toward the middle of the open meadow, where fresh snow covers the tops of ferns and conifer seedlings. Raptor Red feels even more uneasy. The whip-tail seems to be setting up a defense that the raptors don't recognize. Raptor Red gives a low gurgling call to her sister, who looks back briefly, then circles around the far side of the whiptail.

Resource guarding

When a predator rocks up and sees a dead or dying animal, it has to check to see that no bigger ones have claimed it. And when its eating, it has to beware of bigger animals coming to claim it.


It shows you how prevalent bacteria and things wanting to invade you are when you get a tiny cut and it gets infected.

Sometimes it fails and has to lock the open area down and just deal with the invaders already in there. This is called a pimple. It also happens when your skin is being stretches in puberty which opens the pores which lets in impurities which causes pimples.

A scar is skin that's quickly multiplied itself, different from the usual plan for replacing cells. It's the work of the body's rapid response team who've made shortcuts to fill it in quickly to stop infection.

That's how serious infection is, and how prevalent it is.

Why is scar tissue different to normal skin? By Jason G Goldman

In other words, normal skin tissue is constructed of fibres that are oriented randomly to each other, while the very same fibres, in scar tissue, are oriented in a single direction, parallel to each other.

It's actually quite reasonable, from an evolutionary perspective. An open wound leaves the body susceptible to all sorts of problems, from intense pain to infection. So rather than slowly build skin the usual way, scars are the work of the body's rapid response team.

Death from infection

Robert Bakker, Raptor Red

Raptor Red doesn't know why the little chick is dead. Its body lies peacefully in the sand, as if it were napping, not far from the pack's new seaside nest. Raptor Red thinks it is a pretty chick. She always liked it best of her sister's three children.

Raptor Red very gently touches her upper lip against the chick's chest. There's no blood, no visible wound. But the body is cool and stiff. The chick lost an internal battle two hours ago, overcome by a runaway respiratory infection.

Raptor Red has seen death a thousand times. She's watched dinosaur viscera ripped out of still-living bodies. Still, this Utahraptor chick is one of the saddest sights she has seen.

Her male consort is nervous - he doesn't want to be blamed for the death - and he tries to make himself inconspicuous. He sees Raptor Red's sister walking slowly toward him, and he hides between two small dunes.

Genetic fear

As part of their genetic heritage, all species fear that which preys, or preyed on them.

If a species was to gain any power over its environment, this fear may lead them to genocide species resembling that predator that haunted and terrorised them for millions of years.

It's certainly what humans have done. We drove most large land animals to extinction when they migrated and settled across the world. Not just for food either, for ages we've killed predators like lions, wolves, and bears, and worn their heads as trophies.

Even with the extinction of our worst predators (like the short-faced bear, below) people are still instinctually repulsed or frightened by snakes, crocodiles, sharks, hyenas etc. But curiously, not so much bears, big cats, eagles, or wolves. Maybe that's a more recent thing as we've been able to appreciate them at a distance.

Imagine your forefathers running into tigers (the third largest extant land carnivore) over the generations. Imagine how many times they had near-death experiences, but they all survived long enough to have kids.

Imagine the experience, the combination of stealth and power that they would have faced with just primitive weapons. The stripes create a mask which facinates and disorients.


I think that 'monsters' in media tap into this deep seated fear, from the dragons of Arthurian legend to movies. They show a creature that's all teeth, merciless, hungry, and often stronger and faster than us. We're forced into the role our ancestors lived in during the time of the dinosaurs - hiding, nocturnal, running from cover to cover.

In reality though, predators aren't psychopathic creatures. They'll kill their prey and eat their fill, not eradicate everything. Though this doesn't create the most suspenseful antagonist.

We also share the same battles against coldness and hunger… They love their families too, and snuggle up with their cubs.

The original Alien


The short-faced bear



The rain

Water that is too stagnant to drink has given too many microbes the opportunity to multiply.

The proliferation of too much life and the waste it creates, prevents more complex life (like animals) from drinking it and thriving.

Rain destroys the environment the microbes thrive in, but improves the environment for complex life which requires something simpler - water without pollution and waste.

Depending on its volume and ferocity, it also destroys ecosystems for insects all the way up to the large animals.

It also impedes visibility in streams, lakes, and coasts, impeding photosynthesis and plant growth. This starts a period of starvation for aquatic ecosystems.

But it replenishes ecosystems with water, with which plants thrive and grow, providing the ecosystem with renewed food and growth.

It's a cycle of destruction and creation.

Savage garden

H.P Lovecraft describes a mythos where humanity has emerged into a new ecosystem of monsters, each more terrible than the last.

In this new environment, we're less than an insect. We're tiny, short lived, powerless, and inconsequential.

It's a return to our primeval state.

Nature is THE MOST metal, bloodthirsty thing.

Dogs howls. The sound of the hunt. Coordinating with others miles away. The sound of fear in other animals. Not so much the monkeys and birds though. They were in the trees. Maybe they had some symbiotic alliance in prehistory. Maybe that's why us primates aren't worried by dogs barking. For rabbits, however... they might be filled with terror, trapped in their cages. Justified too, considering how often cages are broken into and the rabbits eaten by dogs or foxes.

The savage garden is well named. Monsters WILL murder your children and eat their faces right in front of you. And they'll be back next week. They are scary and truly monstrous.

What are its rules?

They have created:

  • Camouflage, herd protection, speed, armour, intelligence, tools, poison, venom, pack hunting, sheer size, etc. And then there's sex too, which perhaps should be treated as separate again.
  • The first is to thoroughly understand your environment and all of the players inside it. Anything that you've never seen before is generally dealt with according to your current position in the ecosystem.

How do you communicate this?

If you've seen Jurassic Park, imagine  how it would feel to potentially be eaten by velociraptors at literally any moment.

How would that affect your life, if a raptor could just jump on you and eat your face when you walked out the front door? So you start having to sneak out the back. What if they are clever and learn where you like to go to the shops, and how often? You would have to sneak around at midnight, look around every corner, avoid open spaces, wear neutral or camouflaged clothing, and you could never live in something so obvious as a house - you'd have to go up a tree or dig a small hole underneath a bush or rock and live under there.

This is the lifestyle of most small animals, who live in constant fear of dogs, cats, snakes, foxes, bears, and other predators. And it's the story of life - our ancestral species lived through it. Our bodies have been crafted around it. It's called the savage garden, it's the usual state of being on our planet, and almost our entire species has forgotten about it.

Nature has battlegrounds everywhere

Richard Adams, Watership Down

Thunder sunk his teeth into a piece of broken root and pulled it out. There was an instant fall of earth and a gap opened where he had been digging. The soil no longer reached to the roof. It was only a broad pile of soft earth, half-filling the run. Woundwort, still waiting silently, could smell and hear a considerable number of rabbits on the far side. He hoped that now they might come into the open burrow and try to attack him.

But they made no move. When it came to fighting, Woundwort was not given to careful calculation. Men, and larger animals such as wolves, usually have an idea of their own numbers and those of the enemy and this affects their readiness to fight and how they go about it. Woundwort had never had any need to think like this. What he had learned from all his experience of fighting was that nearly always there are those who want to fight and those who do not but feel they cannot avoid it.

More than once he had fought alone and imposed his will on crowds of other rabbits. He held down a great warren with the help of a handful of devoted officers. It did not occur to him now - and if it had, he would not have thought it mattered - that most of his rabbits were still outside; that those who were with him were fewer than those on the other side of the wall and that until Groundsel had got the runs open they could not get out even if they wanted to.

This sort of thing does not count among fighting rabbits. Ferocity and aggression are everything. What Woundwort knew was that those beyond the wall were afraid of him and that on this account he had the advantage.

'Groundsel,' he said, as soon as you've got those runs open, tell Campion to send everyone down here. The rest of you, follow me. We'll have this business finished by the time the others get in to join us.' Woundwort waited only for Groundsel to bring back the two rabbits who had been sent to search among the tree roots at the north end of the burrow. Then, with Vervain behind him, he climbed the pile of fallen earth and thrust his way into the narrow run.

In the dark he could hear and smell the rustling and crowding of rabbits - both bucks and does - ahead of him. There were two bucks directly in his path but they fell back as he ploughed through the loose soil.

He plunged forward and felt the ground suddenly turn beneath him. The next moment a rabbit started up from the earth at his feet and sank his teeth in the pit of his near fore-leg, just where it joined the body. Woundwort had won almost every fight of his life by using his weight. Other rabbits could not stop him and once they went down they seldom got up.

He tried to push now, but his back legs could get no purchase in the pile of loose, yielding soil behind him. He reared up, and as he did so realized that the enemy beneath him was crouching in a scooped-out trench the size of his own body. He struck out and felt his claws score deeply along the back and haunch. Then the other rabbit, still keeping his grip under Woundwort's shoulder, thrust upwards with his hind legs braced against the floor of the trench.

Woundwort, with both fore-feet off the ground, was thrown over on his back on the earth pile. He lashed out, but the enemy had already loosed his hold and was beyond his reach. Woundwort stood up. He could feel the blood running down the inside of his near foreleg. The muscle was wounded. He could not put his full weight on it. But his own claws, too, were bloody and this blood was not his.

'Are you all right, sir ? ' asked Vervain, behind him. 'Of course I'm all right, you fool,' said Woundwort. Follow me close.' The other rabbit spoke from in front of him. 'You told me once to start by impressing you. General. I hope I have.' 'I told you once that I would kill you myself,' replied Woundwort. There is no white bird here, Thlayli.'

He advanced for the second time. Bigwig's taunt had been deliberate. He hoped that Woundwort would fly at him and so give him a chance to bite him again. But as he waited, pressed to the ground, he realized that Woundwort was too clever to be drawn. Always quick to size up any new situation, he was coming forward slowly, keeping close to the ground himself. He meant to use his claws. Afraid, listening to Woundwort's approach, Bigwig could hear the uneven movement of his forepaws, almost within striking distance.

Instinctively he drew back and as he did so the thought came with the sound. 'The near forepaw's dragging. He can't use it properly.' Leaving his right flank exposed, he struck out on his near side. His claws found Woundwort's leg, ripping sideways; but before he could draw back, Woundwort's whole weight came down on him and the next moment his teeth had met in his right ear.

Bigwig squealed, pressed down and thrashing from side to side. Woundwort, feeling his enemy's fear and helplessness, loosed his hold of the ear and rose above him, ready to bite and tear him across the back of the neck. For an instant he stood above the helpless Bigwig, his shoulders filling the run.

Then his injured foreleg gave way and he lurched sideways against the wall. Bigwig cuffed him twice across the face and felt the third blow pass through his whiskers as he sprang back. The sound of his heavy breathing came plainly from the top of the earth pile. Bigwig, the blood oozing from his back and ear, stood his ground and waited.

Suddenly he realized that he could see the dark shape of General Woundwort faintly outlined, where he crouched above him. The first traces of daylight were glimmering through the broken roof of the Honeycomb behind.