most wood species have subspecies. as an example this page shows 13 species of maple..
One of the most familiar genera of trees is maple (Acer). These trees are famous for their fall colors and the dense shade they lend to a landscape.
www.thespruce.com
another factor is how big the tree is and how it grew.
an old growth tree that grew up in a forest, had to compete for light and grew less within each year, so when you look at wood , pay attention to the proximity of it's growth rings. I commonly see fir here with as high as 1/8" per year and some is 100 years per inch, big differences..
another thing is where in the tree the wood is sourced, If it is a long tall straight tree and wood is taken from a straight part of the trunk where there are few branches then the wood's grain is straighter than if it were from near branches, branches mean knots, knots and the areas nearby will have twisty grain patterns.
the straighter and ore consistent grain patterns will bend and twist about less , then straight grain..
I bought a bunch of maple crating lumber and used it for cabinetry, some was so disturbed as it was near knots it had lovely grain patterns.. That's not what you want for a cue unless it is the butt and the grain is used as an attractive feature. perfect wood looks boring. exciting grain patterns are lovely to see..
a lot of those maple planks I ha to rip into about 3" pieces, they would often tend to wanto bind on my blade and even stop my 3 HP saw,, you cna use a splitter or riving knofe to help it not trap the blade.. Id often neeed to flip the board end for end to finish the cut because it squeezed the blade,, this is beacuse the sawcut releases the inherent stresses and the plank finds a new "attitude"
If I second cut all the planks and joint and plane them to be truly straight and set them aside a few days upon return I will see that they have moved further.. to work around that Ill often trim them more than once after allowign time to naturalize.
a cue maker may do similar and turn a bunch of blanks to close to the finished dimension and then let them sit, then he can throw out the ones that went too twisty..
Its never a perfect sciece because wood always has imperfections and stress within it's grain but there are things that can be done which help.
if you pick up 20 50 year old cues and find 2 straight ones in the lot then you are doing more selection,, those couple of cues that did manage to stay straight are probably pretty stable.
go buy some new made in china cue, it may come off a production line and roll straight,, wait ten years, you can likely see the cue warp, but it is a game of odds.
If you find an old cue you can stop and think what the conditions of the forests were like when it was made. As time goes on we will never again see the kind of forest conditions that some of that lumber grew within. A lot of the trees cut 50 years ago were from virgin forests. renewable resource? well not really but we can grow more trees, just not in the same conditions where they grew in competition for so many years and were undisturbed.