
Ant Colonies Retain Memories That Outlast the Lifespans of Individuals - bangonkeyboard
https://www.smithsonianmag.com/science-nature/ant-colonies-retain-memories-outlast-lifespans-individuals-180971022/
======
WalterBright
These algorithms are similar to the ones I developed for the computer strategy
for the Empire game. They worked, but I was unable to get them good enough to
reliably defeat a human player.

The first strategy I tried was simply randomness. It was pretty ineffective. A
rule based one was also ineffective, as it tended to get itself into a box.
But I found that adding a dose of randomness to the rule based strategy worked
well.

Most computer strategies of the day cheated, or altered the rules to give an
advantage to the AI. Empire didn't. I did have thoughts about creating an
interface so people could provide their own AIs and then the various AIs could
battle it out.

classicempire.com

There's been a lot of research on the Life game. But I bet Empire would be a
much better research platform - the rules are simple, but the game play can
get pretty complex. I had a lot of fun developing AI algorithms for it. I wish
the ant algorithms were known at the time, I bet they'd help!

(One of the reasons the simple rules worked so well was the pieces had a
hammer-paper-scissors relationship to each other.)

~~~
swampthinker
Hey Walter, did Sid Meier ever consult you while developing the Civilization
series? I recognized a lot of similarities between Civ and Classic Empire when
I went back and played the older games in the series.

~~~
WalterBright
No, he never acknowledged Empire.

~~~
c3534l
Do you mean he never acknowledged Empire as an inspiration? This article
mentions him admitting that: [https://arstechnica.com/gaming/2017/03/sid-
meier-tells-civil...](https://arstechnica.com/gaming/2017/03/sid-meier-tells-
civilizations-origin-story-cites-childrens-history-books/)

Additionally, I'm like 75% sure I remember him mentioning Empire at a GDC
talk.

~~~
WalterBright
I didn't know he had. Thanks for the link.

------
widforss
I just traversed the ant part of Wikipedia, and this is what I found.

> Queen ants have one of the longest life-spans of any known insect – up to 30
> years.

> The fertile eggs become female worker ants and unfertilized eggs develop as
> males; if the fertilized eggs and pupae are well-nurtured, they potentially
> become queens.

> males are "quickly converted to sexual missiles."

> the queens often try to escape the males, allowing only the fastest and the
> fittest males to mate. Mating takes place during flight.

> One queen usually mates with several males. The sperm is stored in a special
> organ, known as a spermatheca, in the queen's abdomen, and lasts throughout
> her lifetime. This can be as long as 20 years, during which time the sperm
> can be used to fertilize tens of millions of eggs.

> The males have evolved for the single purpose of inseminating the queen.[3]
> During "the quick and violent mating," the male literally explodes his
> internal genitalia into the genital chamber of the queen and quickly dies.

And, moving on to army ants.

> A nest is constructed out of the living ant workers' own bodies to protect
> the queen and larvae, and is later deconstructed as the ants move on.

> As many as 150,000 to 700,000 worker bodies cover and protect the queen,
> linking legs and bodies in a mass that measures a meter across.

> In the morning, the bivouac dissolves into raiding columns that form a fan-
> shaped front. These raiding columns can travel up to 20 metres per hour with
> lead workers laying a chemical trail for other workers to follow. Smaller
> workers lead the column, while larger, formidable soldiers protect the
> flanks.

> When the queens emerge, the workers in the colony will form two 'systems' or
> arms in opposite directions. These queens that are hatched will move down
> either the arms and only two queens will succeed, one for each branch. The
> remaining new queens will be left in the middle and are abandoned to die.

> The whole colony of army ants can consume up to 500,000 prey animals each
> day, so can have a significant influence on the population, diversity, and
> behavior of their prey. [...] About five species hunt in higher trees, where
> they can attack birds and their eggs, although they focus on hunting other
> social insects along with their eggs and larvae.

~~~
kevinventullo
>> The fertile eggs become female worker ants and unfertilized eggs develop as
males

One interesting consequence of this is that _male ants have no fathers_. All
of their genetic code is inherited from their mother, and there is no
variation in what they pass on. This lack of variation in what fathers pass on
means that two ant sisters share 75% of their chromosomes instead of the 50%
you see in most other animals, which some researchers believe is the
underlying cause for the high level of cooperation in ant species
(eusociality).

More reading:
[https://en.wikipedia.org/wiki/Haplodiploidy](https://en.wikipedia.org/wiki/Haplodiploidy)

~~~
BurningFrog
You can also, if you're in a certain quirky intellectual mood, think of an ant
colony as a _single organism_ , since all the ants in it have 75% identical
DNA.

Its body just happens to be physically disjoint.

~~~
jahbrewski
And if you’re in that quirky intellectual mood, could you also think of all of
humanity as being a single organism, since we all share about 99.9% of our
DNA? Certainly a thought I find hard to shake observing cities from the window
of an airplane..

~~~
dogcomplex
I'm not someone who studies this stuff, but I'd wager that the 99.9% thing
isn't quite the same context as the 75% thing, and two ants in the same colony
are more similar than two humans.

Not to detract from your comment about all humans being one organism and
whatnot (hell, maybe ants and our bodies operate on a different level of
consciousness that as specialized intellectual creatures we typically override
woooah mann). I mostly just wanted to fish for more info on this 75% thing
from someone who studies DNA and can confirm my hunch - and maybe has more
info on correlation between DNA similarity and cooperative behavior.

~~~
mcv

      > I'm not someone who studies this stuff, but I'd wager that the 99.9% thing isn't quite the same context as the 75% thing,
      > and two ants in the same colony are more similar than two humans.
    

Exactly. There are several very distinct contexts for discussing percentages
of genetic similarity, and although it's usually clear from context which one
people are talking about, making it explicit would prevent nonsensical
conflicts like this 99.9% vs 75% one.

~~~
callesgg
Its not 99.9% vs 75%

It is more like 75% closer to 100% than 99.9%

~~~
mcv
That's exactly my point. They represent totally different things.

------
AndrewOMartin
This is a lovely article, and I feel there's a lifetime of lessons to be
learned from any colony behaviour. I've recently submitted a thesis on a swarm
intelligence algorithm which exhibits some of these qualities, and the
parallels between the two was a core component of the contribution.

This effect, where something is globally stable, even though all the
individuals that make it happen are unstable is sometimes described as "a
forest whose contours remain the same, as the trees all change".

Consider this algorithm for an ant colony foraging for a good source of food
(this behaviour has also been observed in ants searching for a new nest site):

    
    
      for each ant in the swarm
        if the ant is unhappy
          run to a random ant
          if the random ant is happy
            follow it to its location
          if the random ant is unhappy
            select a location at random
        if the ant is happy
          the ant continues to search its current location
    
       for each ant in the swarm
         the ant searches a tiny of its location, at random
         if the ant finds food
            the ant becomes happy
          if the ant doesn't find food
            the ant becomes unhappy
    

If you run this algorithm you will find a "clusters" of ants form, which is a
number of ants who share the same foraging location. Importantly, and this is
mathematically proven, the largest cluster will form in the location with the
best probability for finding food. This algorithm works even when the
locations change over time and, as in the article, even when the ants which
found the location are replaced with ants who have simply followed other ants
to get there.

The aspect which captured my attention is that there are tiny changes to
individual lines of the algorithm which implement diverse behaviours such as
hill climbing, optimise for exploitation or exploration, and global
optimisation.

The algorithm is called Stochastic Diffusion Search and I'm in the process of
polishing a Python library which implements it and its many variants for a
Show HN :) The repo is here
[https://github.com/AndrewOwenMartin/sds](https://github.com/AndrewOwenMartin/sds)
some info and an explanatory animation here [http://www.aomartin.co.uk/sds-
animation/](http://www.aomartin.co.uk/sds-animation/) and an beta version is
already on PyPi here
[https://pypi.org/project/sds/](https://pypi.org/project/sds/).

Contact me (email address on my profile) if you're interested in using this
algorithm or contributing to the library, it needs snappy C implementations,
and a better explanatory animation!

~~~
newman8r
Could you model this as a cellular automaton? Kind of reminds me of that.
Sounds cool.

~~~
AndrewOMartin
Each ant, or "agent", just needs to store its "activity" (whether its happy or
unhappy) and its "hypothesis" (its current location). You don't even need to
store the hypothesis of inactive agents, so it's pretty minimal as it is, it's
not clear how you would make it a cellular automaton.

I have some ideas, but what did you have in mind?

~~~
newman8r
Take a look at this visualization
[https://www.youtube.com/watch?v=VsHc91IhzdI](https://www.youtube.com/watch?v=VsHc91IhzdI)

There's a repo in the description. Might not be specifically relevant to your
project though

------
robocat
This is an example of an "extended phenotype" as written about in
[https://en.wikipedia.org/wiki/The_Extended_Phenotype](https://en.wikipedia.org/wiki/The_Extended_Phenotype)
by Richard Dawkins (invented the word meme).

Great concept, although harder to grasp than The Selfish Gene.

It is a bit like treating the ants as stateless functions, and storing the
state in the world?

------
amatecha
I mean, I feel like the wording "retain memories" might imply a greater degree
of consciousness/agency than what was actually observed. The "memory" appears
to be some completely tangible phenomenon, as per their comparison of trees
"retaining memory" in the form of a tree growing bark around where a branch
broke off. "Ants use the rate at which they meet and smell other ants, or the
chemicals deposited by other ants, to decide what to do next." , etc. That
said, it's still pretty interesting, and I think we can make some comparisons
about how humans share knowledge/experience and what kind of tangible markers
we use as cues for our own behaviour.

~~~
fmihaila
In certain traffic conditions, bottlenecks can persist for hours without any
apparent cause (i.e., there is no crash or stopped car blocking the road).
Even though the cars entering and exiting the region are changing all the
time, the bottleneck persists. You could say that traffic has "memory". Ant
colonies can exhibit "memory" in a similar way.

~~~
wahern
The traffic example would work better if the bottlenecks persisted even after
an extended period when all cars were removed from the highway.

~~~
fmihaila
The "memory" of the ant colony doesn't persist when all ants are removed,
either. You can't have memory without having _some_ substrate.

------
sandworm101
>> Apr 23, 2014 - Almost 25 years since the Iron Curtain came down, deer
roaming the Czech-German border still balk at crossing areas where electric
fences one lay

[https://www.dailymail.co.uk/news/article-2611585/Deer-not-
cr...](https://www.dailymail.co.uk/news/article-2611585/Deer-not-cross-old-
iron-curtain-boundary-areas-electric-fences-lay-25-years-regime-fell.html)

I also remember a story from the US. A high-security prison was removed, its
razor wire fences torn down. Years later, GPS data showed an outline of the
prison. The deer were still afraid of a fence that they had never themselves
seen.

------
8bitsrule
An interesting definition of 'memory' (and 'history') includes the 'physical
record' that we can decipher.

Anthropologists study 'memories' left behind by ancient cultures that created
artifacts. And the Earth keeps 'memories' of extinct animals in fossils ...
and of geological events in rocks and landforms. DNA and epigenetics keep a
'memory' of lessons learned. Darwin 'remembered' evolution by the study of
species.

There's a valuable lesson to be learned here ... what record will
'digitization' leave behind?

------
leowoo91
Carpenter ants built a nest in my apple tv, it took me 3 days to clear them
out. I hope they don't remember it.

------
mindgam3
Fascinating. First thing that comes to mind is Family Systems theory of
psychology. The idea is the family unit itself is treated as an entity that is
sick, rather than any single “identified patient.” I like it because it
provides a useful model for understanding transmission of observable patterns
like child abuse or other behavioral problems across generations. If ants can
do it for certain types of behavior, it certainly seems plausible that “human
colonies” aka “families” can as well.

------
totalperspectiv
The book A Deepness in the Sky ([https://www.amazon.com/Deepness-Sky-Zones-
Thought/dp/0812536...](https://www.amazon.com/Deepness-Sky-Zones-
Thought/dp/0812536355)) goes really deep (no pun intended) on this idea! I
highly recommend it as some really solid sci-fi. It was full of big new ideas
I had never conceived of before and often found myself sitting down just to
think.

~~~
wallstop
Likewise Children of Time ([https://www.amazon.com/Children-Time-Adrian-
Tchaikovsky/dp/1...](https://www.amazon.com/Children-Time-Adrian-
Tchaikovsky/dp/1447273303/ref=sr_1_1?s=books&ie=UTF8&qid=1544657316&sr=1-1&keywords=children+of+time)),
another piece of solid sci-fi that explores some ideas about the development
of "intelligence".

------
commandlinefan
CRAB: It's too bad, Achilles, that you weren't here last week, when Dr.
Anteater and Aunt Hillary were my house guests. I should have thought of
having you over then.

ACHILLES: Is Aunt Hillary your aunt, Mr. Crab?

CRAB: Oh, no, she's not really anybody's aunt.

ANTEATER: But the poor dear insists that everybody should call her that, even
strangers. It's just one of her many endearing quirks.

CRAB: Yes, Aunt Hillary is quite eccentric, but such a merry old soul. It's a
shame I didn't have you over to meet her last week.

ANTEATER: She's certainly one of the best-educated ant colonies I have ever
had the good fortune to know. The two of us have spent many a long evening in
conversation on the widest range of topics.

ACHILLES: I thought anteaters were devourers of ants, not patrons of ant-
intellectualism!

ANTEATER: Well, of course the two are not mutually inconsistent. I am on the
best of terms with ant colonies. It's just ants that I eat, not colonies-and
that is good for both parties: me, and the colony.

\- Douglas Hofstatder, "Godel, Escher and Bach"

------
qwerty456127
Doesn't almost every community of living creatures retain memories that
outlast the lifespans of individuals?

------
pks016
Nice article. It’s fascinating how the experiences of individuals can shape
the behaviour of the colony in future. (I am interested in studying this in
future.) I think the ants as simple input and output devices i.e. provide
stimulus, get some results. But, the interaction of ants provides the output
to the complex situations.

When one observes the colony while doing any colony related function, one can
see how each individual is assigned with specific function e.g. foraging,
nursing etc. And suppose if you remove these ants, there will be a new set of
individuals doing that function. Somewhat similar to the neurons of brain.
(One has to compare the extent of similarities.)

PS: I used to do research with ants. My master’s thesis was on colony
cohesion. What are the factors important for the cohesion? I have looked at
few aspects (physical) of this.

------
erikb
Is it surprising? We do the same and call this culture. A set of behaviour
rules that we inherit from previous generations, don't really need to
understand but can still use it to increase our survival and which slowly
adapts to big time environment changes.

------
oh_sigh
This reminds me of the parable of the 5 monkeys:
[http://wiki.c2.com/?TheFiveMonkeys](http://wiki.c2.com/?TheFiveMonkeys)

------
rpz
This isnt very surprising me considering we humans--and probably most other
living species--are pretty good at this. Memory seems to be an emergent
property of a network.

------
amelius
Reminds me of this:

[https://skeptics.stackexchange.com/questions/6828/was-the-
ex...](https://skeptics.stackexchange.com/questions/6828/was-the-experiment-
with-five-monkeys-a-ladder-a-banana-and-a-water-spray-condu)

------
marmot777
I’ve heard the concept of a “hive mind” before but this is extraordinary.

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agumonkey
So basically it's a massively legged delay line memory

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cobbzilla
ants have culture, ants have memes.

------
menzoic
culture

