yeah, food supply cannot be the only limiting factor or else the rats and mice would eat up all the grain before the people could and our agricultural ancestors would have starved. Since rodents breed much faster than we do.The purpose of having a cat on your farm isn't to eradicate the rodents in the area. It's to prevent those rodents from eating your food supplies. Cats are effective at this. (They would be more effective if they could be trained to stay in one place instead of roaming as they do, but still, their presence and even their odor has been demonstrated to frighten rodents away.)
The second half of what I quoted in no way contradicts what I stated: "Second, there may be compensatory changes in the growth, survival or reproduction of the surviving prey: they may experience reduced competition for a limiting resource, or produce more offspring, or other predators may take fewer of the prey (Emphasis mine)." Preyed upon species experience reduced intraspecies competition for food, shelter, and other resources, but the primary limit as you'll note is still that of food, shelter, and other resources (as is noted elsewhere in the text I quoted from). Intraspecies competition - self limiting - is the primary limitation of any species, which you'll note is stated in any Ecology text.I am familiar with basic ecology. What you have quoted is the caveats explaining why sometimes predators have less effect than you would expect from their raw kill numbers. Not an isolated statement about how predation cannot be a limiting factor. Also have you noticed that the second half of this counters your initial thesis, because it points out that predation can release a population from being limited by resource scarcity aka predation becomes the new limiting factor on the population.
The statement I would like you to demonstrate your initial one
Sometimes a primary consumer is limited by predation and so this statement is false.
Rodents are after all primary consumers which means the primary limiting factor for them is resource scarcity and not predation.
You'll note I've never stated that other things can't play an impact on population size, but the biggest and primary limitations are resource scarcity owing to intraspecies competition. Pressure from predators is secondary and in the best cases only depresses the population a bit below the environmental limit, and as in the case of rodents the research consistently shows no effect whatsoever. Research on rodent population shows that rodent population size is largely constant with or without predation, which is to say that cats aren't effective at rodent control.Primary consumers are primarily limited by resources. Primary consumers expand to the limit of their environment in food and shelter, the natural scarcity of resources in the environment is what limits primary consumers - primary consumers biggest limiters are themselves.
Thank you, I was wondering about that.There is no group of humans anywhere that doesn't interact with the dogs.
And as meat, themselves.It also means less meat as dogs were used in the hunt and as guard animals.
Any sign of dogs in Neanderthal or Homo Erectus locations?I don't know if there would have been any significant impacts to human development had they never been?
maybe not on a population level, but, as mentioned bywhich is to say that cats aren't effective at rodent control.
Cats can be replaced with snakes and ferrets and foxes
Perhaps they could have domesticated rats to hunt mice?Could humans have just domesticated mice instead of cats?
This assumes the overkill hypothesis is true, which I have my doubts about. My pet theory (though of course I can't prove it) is that Native Americans increasing the occurrence of fire in the landscape made it more hostile to megafauna, which combined with climate instability drove them to extinction.Would that mean a megafaunal survival in North America, of at least a few more species, if Paleo-Indians don't have dogs to help them hunt?
Perhaps they could have domesticated rats to hunt mice?
This probably could have been done, but would have been difficult and time consuming.
As although rats could hunt mice, unlike cats, they are omnivores and would have much easier food around they could eat than hunting mice.
You've just proven your point. Dogs are used to hunt rodents. Without cats, they would most likely be used more regularly for such purposes.Without cats, could dogs be adapted for rodent control? OTL terriers can be extremely efficient ratters because they will hunt and kill even when not hungry.
Dogs do hunt rodents sometimes, but it is more complicated than this. Mice have an instinctive fear of cats, and the smell of cat urine/markings will, alone, strongly discourage them from an area. This is the main benefit that cats bring - much more than the number of rodents that they kill, which is low.You've just proven your point. Dogs are used to hunt rodents. Without cats, they would most likely be used more regularly for such purposes.
Fair.Dogs do hunt rodents sometimes, but it is more complicated than this. Mice have an instinctive fear of cats, and the smell of cat urine/markings will, alone, strongly discourage them from an area. This is the main benefit that cats bring - much more than the number of rodents that they kill, which is low.
While a dog can certainly scare rodents, they do not seem to have quite the same instinctive fear of them. In fact, there is evidence that dog droppings can even attract them.
No "could" about it. Humans do eat rats.Could humans eat rats?
The problem with domesticating rats is that they can chew their way out of more or less anything.But yes, domesticating of rats is pretty unlikely on early stage of human civilisation. No one seen them anything else than pests and hardly most of people have much better view even nowadays altough there is already pet rats.
And it might be problem that they re-produce extremely rapidly.
Perhaps they could have domesticated rats to hunt mice?
I guess I was thinking of guarding the house rather than the grain stores, but you're right, for pre-industrial people that would be the biggest concern.I wouldn't trust a rat to guard my grain stores. They're as likely to eat the grain as the mice are.
maybe not on a population level, but, as mentioned by
@funnyhat, how are they at keeping the rodents away from the humans?
That's the point I keep trying to make. I know people are raised thinking cats are good at dealing with mice, because individually they are, but it doesn't actually matter. Mice are a minor nuisance in a home (and you can trap mice at that level just as effectively as cats can kill them). Keeping them away from humans doesn't really matter, because the crop losses are coming first in the field (where they to this day remain an issue) and where its stored.I guess I was thinking of guarding the house rather than the grain stores, but you're right, for pre-industrial people that would be the biggest concern.
If they're not reducing numbers then they aren't actually helping anything, because they're not actually reducing food consumption by pests. In spite of the common assumption that cats reduce rodent numbers, there's strikingly little scientific evidence to actually support that assumption. Cats get a great deal of benefit from humans, but the same is not necessarily true of humans getting benefit from cats. Cats exist in a commensal relationship with humans, just as dogs exist in a mutualistic relationship and rodents a parasitic relationship. All three are symbiotic, but they're very different forms of symbiosis.The purpose of having a cat on your farm isn't to eradicate the rodents in the area. It's to prevent those rodents from eating your food supplies. Cats are effective at this. (They would be more effective if they could be trained to stay in one place instead of roaming as they do, but still, their presence and even their odor has been demonstrated to frighten rodents away.)