

How many cats you'd have if you had 1 female and left it with males for 5 years - slater
http://stu.ie/?p=2541

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keenerd
Completely inaccurate, at least for where I live. If it were true, the world
would be a much less sad place. But reality cares not for cute kittens.

Here in the northeast US, feral cats (or even indoor cats with a comfy life)
will never have two litters in a year. You are guaranteed one per year though.
Maybe in Florida things are different.

Most kittens will never survive. We "had" one very feral cat. She would not
even touch food we left out, until she was 20 years old and had cataracts in
both eyes. Her secret to a long life? Dump all the kittens. Don't even let
them nurse if you can help it. She had a dozen litters over the years. Most
all died within two months, the lucky few lasted six. We buried all the ones
we could find. Only one kitten of all her litters made it past a year.

The half life of a feral kitten is around three months. With a typical litter
of five (including the runt who will get abandoned at a few weeks), maybe one
will make it past a year. If no one starts feeding the extra cat, it won't
even make it that long.

Edit: One final note. The life span and litter size of cats is very close to
that of squirrels. True, squirrels have less environmental impact, being
herbivores. (But this just means an environment could support an even larger
number of squirrels.) The world is not drowning in squirrels (except for maybe
Cornell) despite no one ever fixing the squirrels on their property.

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zeteo
Right, so cats are close to an r-selection strategy:

<http://en.wikipedia.org/wiki/R/K_selection_theory>

If you were to do the same calculation with fruit flies, or even bacteria,
you'd probably reach the number of atoms in the universe (~ 10^80) in less
than five years. For various reasons, the exponential will turn into a
logistic curve pretty soon (unstated assumptions of the article include the
availability of food, water, space and the absence of predators).

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f1gm3nt
Source code would be cool. With some tweeking you could edit the source for
other animals. Is there any other stats formula out there that does this kind
of thing?

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farmerbuzz
Differential equations are great for modeling these sorts of problems.
<http://www.geom.uiuc.edu/education/calc-init/population/>

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houseabsolute
Of course the biggest shortcoming of all is that breeding will quickly outpace
the food supply and many cats will starve to death or die of other causes
without having reproduced.

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pavel_lishin
Realistically, sure, but if someone were really determined to carry this out
in real life - let's say, the government of Thailand for no real reason -
they'd be able to afford to feed 10,000 cats pretty easily.

Oh, and what if we assume that the cats can or will eat each other, or corpses
of other cats?

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eavc
Feeding 10,000 cats--not that hard.

Getting 10,000 cats to breed optimally--pretty much impossible. Heck, try
getting three of them to optimally not fight each other for a week at a time.

~~~
absconditus
This is your man:

<http://www.youtube.com/watch?v=6VswBKrPuAQ>

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Empedocles99
There was an article about this in sfgate two weeks ago.

It's pretty much a fantasy, madeup statistic.

<http://www.sfgate.com/columns/yourwholepet/>

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trouble
If the entire cat population after five years originated from one female I
think the total would be somewhat less than that estimated due to negative
genetic effects - mainly inbreeding depression:
<http://en.wikipedia.org/wiki/Inbreeding_depression>.

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mikecane
Thing is this: 1) not all survive out of a litter, even after several weeks,
2) if a cat has litters too close together, she will often refuse to nurse the
second litter and they will all die. If everything that gave birth by litter
survived, we humans wouldn't be here.

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malabar
It is possible to have dozens or more, since the female cat can have a litter
from multiple sires. A female cat can mate with multiple tom's during the
estrus (7-21 days) or heat cycle.

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zepolen
I don't understand why it took over 3 hours to simulate 1000 iterations, I'm
sure this could be done much more quickly, even with perl.

Wish the author would post source code.

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gojomo
Next month -- October 16 -- is National Feral Cat Day:

<http://www.alleycat.org/NetCommunity/Page.aspx?pid=388>

(If you feed strays without also pursuing trap/neuter/release you may be just
multiplying the misery.)

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naelshawwa
neat experiment! lol

