3036: Chess Zoo

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Chess Zoo

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Title text: The zoo takes special care to keep kings separated from opposite-color pieces as part of their conservation program to prevent mating in captivity.

Explanation

This explanation may be incomplete or incorrect: Need to move the image in the trivia inside the explanation in a smooth way. It's not trivial, it's useful for the explanation. If you can address this issue, please edit the page! Thanks.

Zoos are large encampments where various animals live in small enclosures. They're generally used as public exhibitions for amusement and education and as safe spaces for rescued and endangered animals. Many modern zoos deliberately allow different types of animals to mingle and interact, finding that it promotes enrichment and well-being. Naturally, in such cases, the zoo needs to be designed so that incompatible species (such as predators and prey) aren't allowed to interact, and good designs will allow animals space for rest and privacy when needed.

Randall has created a zoo for giant chess pieces, treating them as if they were animals. He designs the enclosures to allow interactions between different species, but prevents the possibility of one piece capturing another (which is treated as analogous to one animal attacking another), as well as of escape. In the Trivia section, a coloured version of the zoo shows where different types of pieces can move. The zoo is almost completely horizontally symmetrical from top to bottom with black pieces on the top and white pieces on the bottom. The only place that isn't completely symmetrical is the entrances to the bishop enclosures.

There are many subtle "jokes" in the image that play on how chess pieces move:

• ♗ Bishops can only move diagonally. Enclosures containing them do not have diagonal walls or corners which would allow them to slip out, and orthogonal portals into their enclosures are only one square wide and at least two squares long so that they can't get through. One bishop enclosure even has a portal open to the visiting people, letting it serve as a petting zoo. Opposing bishops can safely mingle as long as they are on opposite colors, since a bishop can never move to a square of the opposite color than the one on which it currently stands. This is enforced by these mingling enclosures only having two openings, each on opposite colored squares (i.e. an enclosure only has an opening for black pieces on white squares and one for white pieces on black squares).
• ♘ Knights move in an "L" shape (two squares along one orthogonal direction, then one more square in a perpendicular direction), leaping over other pieces and presumably walls. The walls of their enclosures have been designed to prevent escape by placing blocks where they would land if they leapt over the wall, or using double-thick walls. They can also be blocked by the same portals that block bishops, although they would need to be four blocks long instead of two.
• ♖ Rooks can only move along ranks and files. They have free roam of several enclosures, though diagonal walls are able to stop them, preventing them from accessing the center mingling bishops.
• ♕ Queens and ♔ kings can move along ranks and files as well as diagonally, so their enclosures must have the same precautions as would be required for both bishops and rooks.
• ♙ Pawns can only move forward (or diagonally forward when capturing), but upon reaching the final rank (the opponent's back rank), they are "promoted," becoming a knight, bishop, rook, or queen. The pawns are in a double-walled enclosure with no doors to prevent escape after promotion.
• A special feature of the enclosure, mentioned in the caption, is that there is at least one room for every type of pieces where other pieces cannot enter (except the king is always in a room with the queens). This means that even though some of the pieces can mingle with some of the other pieces they can also always retreat to a room where the other pieces cannot disturb them. For instance the top and bottom room with rooks can not be entered by any other type of pieces. In the two rooms right above and below the middle room, the bishops of the same color have their personal room. And also the two rooms to the right where black and white bishops co-exist on different colors, cannot be entered by any other type. (This is of course needed, since else there could be captures). The pawns have their own rooms top and bottom right. The knights have a separate room from which they can jump out to the rooms with either rooks or king/queens, but no other piece can enter their personal space to the left. And the king and his queens can retreat top or bottom left where the knights cannot enter. No piece can encounter all the others (even of the same color) but all pieces can meet at least one other type of pieces, the pawns though only after promotion. But they could not meet a king. This is similar to real zoos where separate enclosures are designed to be accessible only to one species (for example, through an opening too small for one of the species to pass through), allowing animals control over their interactions.

It is unclear what would happen to the pawns after they are promoted. Whether they remain in the "pawn" enclosure or moved to their new enclosure according to their new piece type is not indicated. Also unsure is how the pawns would be repopulated if all of them were to be promoted, leaving the pawn enclosure devoid of pawns. It appears that the pawns promoting is part of the zoo's attractions as mentioned in the Banner for the black pawns' enclosure that reads "SHH! PAWNS PROMOTING." It is not explained why the visitors would need to be quiet, but if the logic of treating the pawns like zoo animals is extended then loud and rowdy humans would likely distract, disturb or otherwise prevent the pawns from promoting. Alternatively, perhaps the pawn promotion process produces some sort of cute noise, and if visitors are quiet they are more likely to hear it.

There are a couple of "interaction" areas that could have been built into the zoo design while preventing piece capture or escape but have not. There is no reason bishops and knights of the same color couldn't occupy the same enclosure, so long as there are adequate walls to prevent knights from escaping their enclosure. Additionally, it would be possible to allow visitor access to the white-bishop-on-black and black-bishop-on-white enclosure, as well as allow visitor access to the knight enclosures, however it is not apparent whether this is a priority of the zoo.

Every visitor of the zoo is depicted as centered on a single square occupied only by themselves, just like a chess piece. This could perhaps imply an entire chess board "world", where humans and chess pieces coexist as separate species, both aligned to the grid.

The title text contains a pun on the word 'mating'. The phrase "mating in captivity" is typically used to refer to animals in zoos copulating, hopefully producing offspring. This is typically done for species that are endangered (in hopes of reintroducing them to the wild, and in the meantime maintaining a healthy population of their own), but in the relatively safe and nurturing environment of the zoo could become problematic if allowed to happen without a certain degree of planning. In a conservation program, much thought may be put to how to avoid inbreeding, overpopulation and social stresses amongst the animals (as well as the problems of feeding and housing all the offspring), and so males and females may be given limited and highly curated access to each other, strictly according to the identified breeding requirements.

In the context of chess, "mating" means delivering an attack from which the opponent's king cannot escape, thereby winning the game. Unlike captive breeding programs, "mating" in in this sense, would presumably eliminate a piece (or an entire side), rather than creating additional animals, and therefore is undesirable. To prevent this from occurring, kings are not kept in the same enclosure as any piece of an opposing color. In fact, only opposing bishops on opposite colors are shown as unallied co-residents of an enclosure, in this zoo, thanks to their particular method of wall-free separation.

Transcript

[A large panel is shown. It contains what appear to be a chessboard, but it is much larger than the usual 8x8=64 chess board squares. But it is divided into squares that are alternatingly white or gray. In the part shown 29x43 = 1247 squares are visible. Although for the outer rows and columns only less than half of each square there can be seen, so only 27x41 = 1107 squares are fully shown. On the "board" there are many details. Above the panel there is a large caption with a caption giving an explanation:]

Chess Zoo

Designed to give different types of pieces their own enclosures while letting them interact as much as possible without allowing captures

[Upon the board there has been drawn an enclosure by drawing black squares on the white/gray squares. These black squares are smaller than the underlying squares but centered on the middle of their square. The outer parts of this enclosure covers 25x39 = 975 squares. It is not an entire rectangle of the black squares, but the top, the right side and bottom is a full line of 25, 39 and 25 black squares. The left line is only a normal line for the top and bottom 6 squares. Then for the next 12 rows (top or bottom), the "solid" line is moved one step in (to the right) and only on every second row is here a black square on the outer line. Above this there is a gap of 5 squares without black squares on either of the two left most squares (and 7 rows in a row with no black squares on the outer most line). This created a section inside the enclosure connected directly to the outside, but this part is still closed off, with black squares forming walls on this inner section, that closes it off from the rest of the enclosure.]

[Inside this enclosure there are many other squares that have the black squares on top forming several rooms that are either closed of from other rooms or connected in some places. And on the white and gray squares that do not have black squares in top, there may bee drawn chess pieces or humans on them.]

[The top part of the image has enclosures for black chess pieces and the bottom for white ones. Smaller black squares form enclosures around the chess pieces while the characters are outside of them. In the middle of the image, to the right, there are black and white bishops next to each other on squares of opposite colors. Humans are only on the outside of the enclosure, mainly above (eight) and below (six) with only three to the right. The the left people can stand either outside normal (three), or inside one of the indentations (two). But they can also walk into the open part and there are nine inside like this.]

[Banner on top of smaller black squares on the top right, above an enclosure with a knight and four pawns:]

Banner: Shh! Pawns promoting.

[Jill near the center, standing in front of Blondie and pointing forward:]

Jill: Look, mommy! Bishops!

Detailed description

[The humans outside the actual part of the enclosure are listed here, and the rooms they are looking into are also described:]

[Top row from the left: Over the fifth black square a boy with what appears to be a cap. Next to him Hairbun. Two squares over Cueball. They look into the blacks King and Queens only section. There are four queens in this room and the king. One of the Queens are on her way down a hall to a room below, with a fifth queen and a knight. Over black square 14 there is another Cueball next to Hairy looking into the black rook only section. There are three rooks, one of which is moving in a hall to the room below. Over black square 19 is White Hat and two squares on Danish next to Ponytail looking into the black pawns only section, the two women over the banner. One of the pawns has promoted into a knight four others are still on their way to promote. This room has double thickness walls with two black squares all the way around.]

[Down the right side from the top: To the right of black square 12 from the top another Cueball looking into the blacks bishops only section with three bishops, two on gray squares and one on a white square. To the right of black square 26 from the top another White Hat and another Hairy are looking into the white bishops only section with two bishops both on white squares. Above this room is a room with both white and black bishops, with the three white bishops on gray squares and the three black bishops on white squares.]

[Bottom row from the right: Under the fourth black square from the right another Cueball looking into the White pawns only section, there are three pawns, none of them has promoted, bu their is also no banner- This room also has double thickness walls. Under the tenth black square to the 13th are four people in a row, from the right, another White Hat, another Hairy, another Hair Bun and another Cueball. They look into the white rooks only section. There are four rooks, one of them on the way into a hall towards the room above. Under the 21st black square from the right Megan is looking into the white King and Queens only section. There are three Queens with the King. A fourth queen is in a room above, where she is together with a knight.]

[Up the left side from the bottom: The the left of black square three from the bottom another Hairy is looking into the white King and Queens only section. The seventh black square from the bottom it moved on space to the right. In the hole left there another Cueball is standing so he can see the passage where the white King and Queen can move into a room where also white knights can be, and there is one knight and one queen. To the left of outer wall 27 squares up, is Blondie, she is standing in the normal row left of the wall, but at a place where there is an indentation, so she is not next to the nearest black square. Se looks into the black knights only section with only one knight present. Four squares above her another Ponytail is standing in an indentation in the wall looking into the room where the black King and Queens can be together with the black knights, there is a queen and a knight. Four squares above this another Hairy is seen. He seems to have turned away from the wall walking to the left, so he is not looking into the black King and Queens only section behind him.]

[The opening into the enclosure from the left to the end: Three squares in at the bottom over a black square one higher than the nearest another Megan walks to the right, next to her another Cueball walks the same way, he is not directly over a black square. And one further left below in one if the indentations another Ponytail. They are all above the white knights only section, with only one knight present. Above the first of the two Cueball's at the top of the opening in an indentation is Knit Cap looking into the black knights only section. At the bottom four squares further in than Ponytail is a person standing in an indentation with very large hair looking into a room where both white knights and rooks can be together, one of each is present. One further square in but two above him is another Blondie and next to her Jill pointing at the room with white and black bishops together, as she calls out. This room is the one where they are on their own color square, three white on white and three black on gray squares. Above them is the room where both black knight and black rooks can be together, with three knights and one rook. One square further in and one below them is another Cueball looking in to a section only accessible to white rooks next to the bishops room. There is one rook there. But below this part of the room it opens up and has both white rooks (3) and white bishops (5) with three bishops on white and two on gray squares. A similar room is above these last three persons with a black rook in the near part not accessible to bishops but then black rooks (1) and black bishops (3) can be together in the rest of that room. All bishops on gray squares.]

[In total there are 9 Cueballs, 5 Hairys, 3 White Hats, 3 Ponytails, 2 Megans, 2 Hairbuns, 2 Blondies, 1 Knit Cap, 1 Danish, 1 Jill, 1 kid with a cap, 1 man with lots of hair, for a total of 31 humans.]

[In total there are the following black pieces 1 king, 5 queens, 6 knights (one a promoted pawn), 5 rooks, 11 bishops and 4 pawns (together with the promoted knight). A total of 32 black pieces. There are the following white pieces: 1 king, 4 queens, 3 knights, 9 rooks, 13 bishops and 3 pawns for a total of 33 white pieces. 65 pieces in all. Similar number of each type of pieces as there are humans, 31, 32 and 33 for a total of 96 squares occupied by something that are "alive".]

Visual-aspects-reliant representation of the comic

[Layout (H is a human; # is a smaller black square; chess pieces on the top half are black and below that white, unless otherwise noted):]

     HH H     HH   H HH    
 ######################### 
 #         #     ######### 
 #  Q  Q   # R   ##     ## 
 #      K  #    R##P   P## 
H# #Q#    Q##### ## P   ## 
 ### ###       #R##  P  ## 
  ## ######    # ##   N ## 
 ### # #####   # ######### 
 H# Q  #  #### #  ######## 
 ###  N#   #####     #   # 
  #    #  R      B   #   # 
 #######   ####     # B B#H
H #    # N N##   B R#    # 
 ### N #    ##      B# B # 
  #    #    ## #  #  #   # 
 ### # #N# ### ###B## #### 
  ###########  #   B#   B# 
   #H# # # # #R#    #    # 
              ##B   #  B #  [White bishops]
     H     HH     B #  B #  [Black bishops]
   HH        H##  B # B  #  [Left bishop: white, right bishop: black]
   # #H# #H# # # B  # B B# 
  ########### R#    #    # 
 ### # # # ### ## #### ### 
  #   N#    ## # #B   #  # 
 ###   #    ##R    R  #B #H
  #    #    ##   R B #   #H
 #######  R####      # B # 
  #    #          BB#    # 
 ###QN # N ##### B  #    # 
  #    #  #### #  ######## 
 ### # #####   # ######### 
 H## ######    # ##     ## 
 ### ###       # ##P    ## 
 # # #     #####R##     ## 
 #      K Q#     ## P  P## 
H# Q       #  RR ##     ## 
 #  Q      # R   ######### 
 ######################### 
     H       HHHH     H

Trivia

• User D5xtgr made the following depiction of the board with colors showing which rooms the different pieces can enter by mixing colors.
  • It was uploaded here with help, as D5xtgr could not at the time upload files:

• This is a version of xkcd 3036 "Chess Zoo" with partially-transparent coloured overlays illustrating the range of movement each piece has. Warm colours (red, brown, orange, yellow) are used for the black pieces, and cool colours (blue, teal , cyan, green) for the white pieces to show contrast. Because some regions are accessible to multiple pieces, these overlays overlap in places, producing colours that are combination or mixture of the originals.
  • The text taken from the page where the original image was posted.
• Jake Ouellette made an interactive simulation of the chess zoo, which has several more jokes embedded in it.

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Discussion

For the transcript, I’m thinking of saying that “there are alternating white and grey squares, with smaller black squares imposed on them. The pattern of squares goes [something like GWBWGWBWGBW]“. Would that work? Or is it too confusing? 42.book.addict^{Talk to me!} 19:03, 10 January 2025 (UTC)

Re: "GWBWGWBWGBW", knowing who we are here, I presume people might want to distinguish black-on-white from black-on-gray. We'd probably have to have a full markup system for background (gray/white) and foreground (empty, human, barrier, white pawn, gray pawn...). Maybe something like {[gE][wE][gB][wQg]}... Hrm... Because, of course, it has to be as complicated and precise as possible. :) 172.70.46.135 19:15, 10 January 2025 (UTC)

I don’t really like the current transcript because I believe that it’s more confusing to read than my version. Anyone have thoughts? 42.book.addict^{Talk to me!} 23:28, 10 January 2025 (UTC)

Although I do have a suggestion for the transcript: instead of having “H” as a representation of a human, we can have C for Cueball, H for Hairy, P for Ponytail, W for White Hat, D for Danish, M for Megan, and K for Knit Cap. We could also have Unicode black squares instead of the “#” and color the pieces with span. Thoughts? 42.book.addict^{Talk to me!} 00:14, 11 January 2025 (UTC)

I don't think it's safe to allow people to go into the bishop enclosure, especially with high aggression in that area since both colors are able to look at each other there but not capture. One of those bishops is eventually going to take it out on someone. --162.158.90.210 19:34, 10 January 2025 (UTC)

I don't know how dangerous they are to visitors in general, but I wouldn't leave children with them unattended. Maybe the enclosures with the knights would be good petting zoos. Barmar (talk) 19:49, 10 January 2025 (UTC)

Thank you for reporting the bishop feeding gate being open, as this was the fifteenth time the one responsible failed to close it after feeding, he has been summarily fired.172.70.47.106 20:02, 10 January 2025 (UTC)

Depends - they're only dangerous in the proselytising season.172.68.186.43 14:41, 13 January 2025 (UTC)

The zoo seems to be missing an area for knights and bishops to interact. (It has a knight/queen area, a knight/rook area, and a rook/bishop area. It can't have queen/rook or queen/bishop areas if it wants to have areas for rooks or bishops that exclude queens, because nothing blocks queens without blocking rooks and bishops. But it could have a knight/bishop mingling area, accessible to knights via wall-jump and to bishops via a diagonal corridor, and it doesn't.) 162.158.187.84 20:07, 10 January 2025 (UTC)

Similarly, couldn't the pawn promoting zones be more centrally located each side, and have passages respectively for queens/rooks and for knights? Of course then those could enter and interact with promoting pawns, but why would that be deemed a problem? --172.69.222.164 20:41, 10 January 2025 (UTC)

No because it a promoted queen can come into a zone with rooks then it can also get into the bishops room and then enter the opposing bishops room and take them and then get to take opposing rooks and knights as well. It would also be hard to keep knight's out of the opposing side if they get into the bishops area, it would take a lot of wall space. --Kynde (talk) 10:52, 12 January 2025 (UTC)

I believe a knight-knight interaction zone of opposing colors is also possible if correctly designed (such as a 2xn corridor with a particular entrance 162.158.154.52 03:11, 11 January 2025 (UTC)

It would have to be a very restrictive zone. In the case of the 3x3 of 839: Explorers, any knight not on the centre-tile could technically take (or be taken by) any other such knight of that was also there (and not on the centre-tile). Though any knight in imminent danger could of course move to not be (the knight that posed the danger could then move to repose that danger, and they dance around the board in octagramish 'circuits'.

I would propose, though, that a limited-jump entry from two adjoining enclosures to land knights onto a 2x3 'shared enclosure' could work, such that they can't jump to any more thn their two opposite corners (thus also never jump out of it into the other's 'normal' enclosure). And, in my head, I'm imagning a form of zig-zagging diagonal that might extend the area without overlapping the (though intermingling, as with bishops) the viable landing zones. The following is a quick (and probably incorrect, if you spot the probable errors I've not handled correctly) method of mingling two sets of knights (1 & 2, mostly given free reign to top left and bottom right) between walls (#) and various other 'open' squares (.) that could be something else.

2222###........
2222#######....
#2###21#####...
#####122#1##..#
#.####212######
....###221###1#
.....###122#111
......###21##11
.......#####111
........#.#1111
.........###111

In fact, with a narrower corridor, I believe I could constrain two sets of knights to travelling mutually non-antagonistically across a nominally intermingled diagonalised 'neutral-zone', plus send a viable 'bishop corridor' (in fact multiple bishop-corridors!) across in the other diagonal, but then it'd have to be a far less generous pseudo-shared area for the knights, and wouldn't look even as good as the above. 172.68.205.123 00:11, 12 January 2025 (UTC)

You can have some interesting shaped-areas for knights too, not just corridors; you can trivially put two knights together by blocking one of them from moving at all, the interesting question is how to give them both the most freedom of movement, safely, and/or the minimum number of 'blocks' for a given area. e.g. [1] JeffUK (talk) 11:24, 13 January 2025 (UTC)

You can't have same-coloured knights also enter into an opposites-of-bishop shared space, because for all the wish to have shared (overlapping but not congruent) spaces for pieces of the same colour but different limitations, the presence of the anti-bishops would mean contention with the pro-knights.

The fact tht the pawn-enclosures are totally without any same-set pieces (well, apart from the knight, but that was from a promotion) does seem to suggest there's a lack of possible mixing going on, I know. But, the way I read it, if heterochromic pieces can be 'mixed', then they can (which effectively is just the two different ecclesiastical compliments), with homochomic ones then also being allowed to mix if they can do so in a way such that they have all of an "A and B" area, an "A-only" area and a "B-only" area (it's a bit more complicated than that with the kings and queens, as they can traverse all of the same areas as each other, plus the lobe of knight-area which overlaps, but you have "knight+royal", "royal-only" and "knight-only").

Though I can think of one such sharing-situation I would mark down as missed: i.e. a pawn sharing a space with bishops and/or knights with a bishop-/knight-proof corridor 'directly forward' (and, of course, no sideways movement allowed by the pawn), giving the pawn both its unique space and shared space and only-the-other-piece spaces off to the sides. Though, the whole promotion prospects means that just about anything could 'suddenly' be in the pawn-only space, thus sending potential knights/bishops into that 'by proxy'.

...or maybe I've not extrapolated Randall's precise methodology here, but I believe I've accounted the general limitations he seems to have worked to. 162.158.33.215 00:57, 11 January 2025 (UTC)

I don't have permissions to upload an image to this wiki, but if anyone who does would like to copy it over, I illustrated each piece's range of movement here[2]. D5xtgr (talk) 20:09, 10 January 2025 (UTC)

I have put the picture in a trivia section --Kynde (talk) 11:03, 12 January 2025 (UTC)

The plan of the zoo looks like opposing Lewis Chess Men! Nicholasbailey87 (talk) 23:28, 10 January 2025 (UTC)

the transcript needs to be descriptive rather than a text-based diagram so it's screenreader accessible. if someone thinks it's necessary they can move the ascii art to the description. 172.68.71.101 23:40, 10 January 2025 (UTC)

A knight recently escaped. When asked for comment, the director of the zoo said "!?" 172.68.70.134 01:07, 11 January 2025 (UTC)

This is actually a sokoban chess puzzle, where the pieces can push the blocks. White to move and mate in 47.172.70.214.205 02:40, 11 January 2025 (UTC)NickM

In the UK there is a famous zoo called "Chester Zoo", comic readers from the UK will think there is a pun.--Doctormo (talk) 03:46, 11 January 2025 (UTC)

In Russian, chess knights and bishops are literally called horses and elephants. 172.71.148.59 10:40, 11 January 2025 (UTC)

I don't think that the 'same portals that block bishops' can block knights, not without being longer. A knight could get through the 'petting zoo' portal to the bishop paddock. But there's another example below and to the left of a similar portal but much longer that DOES prevent the knights from passing. 172.71.194.90 14:21, 11 January 2025 (UTC)

Do I need new glasses or did the black king escape? 162.158.95.97 17:15, 11 January 2025 (UTC)

Look at the third visitor along at the 'top', then go straight down. Maybe less obvious as the dark pieces hide their internal details more, leaving just their fuzzy (depending on zoom level) outlines. 172.69.79.164 21:10, 11 January 2025 (UTC)

It looks like the transcript has switched the K's and Q's. The king is the piece with the cross on his crown. See Staunton chess set. --172.68.54.157 22:01, 11 January 2025 (UTC)

It’s too bad it couldn’t have somehow allowed castling, or maybe it could’ve just pretended it did. I would’ve appreciated title text that mentioned an incident involving a king escaping its enclosure despite their best efforts due to emergent behavior from unanticipated interaction between differing pieces and Jeff Goldblum saying that nature will find a way. SammyChips 18:00, 13 January 2025 (UTC)

If castling is only blocked by pieces and not walls, Black could still do it if neither the king not bishop to the right of it had moved previously 162.158.41.72 18:04, 13 January 2025 (UTC)

I believe the problem would be with the rook, which would need to occupy the wall space that the king skipped over, unless the process of castling was generalized some to allow different magnitudes of jumps, even if the requirement for lack of movement was ignored. SammyChips 18:23, 13 January 2025 (UTC)