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View submission: How do genes get passed down?
Some physical characteristics are mistaken for genes, but they're not caused by any genes. Some people are said to have big/small facial features, or a long/short torso, limbs, etc, and sometimes there's a misconception there's genes that cause big/small features which are passed down. The human body grows in height/bone structure from 0-13 approx for girls, and 0-20 approx for guys, and it goes through puberty after the bulk of height/bone structure is done. So if someone is observed to have big/small physical features like facial features, torso, limbs, etc etc, it's not always that the feature is large objectively, but compared to the rest of their body it's large.
This could be because a person didn't get enough nutrition/rest etc, when the body was in a certain stage of growth, but got more nutrition afterwards. An example is that some humans who were undernourished in childhood are at stunted adult heights, but they have a larger skull in comparison to their bodies (whereas children of the same height as them tend to have smaller skulls) because the skull kept growing a bit more after their bodies finished growing. It's not possible to control the body's growth. Often if a human is undernourished whilst they're growing up the body could try and hang onto the growing phase for longer, so if they get right nourishment, they'll catch up in growth. But it's possible to be undernourished enough the body cannot delay the growing phase anymore and they'll end up permanently stunted in some way.
However, growth is also caused by genes which are passed down from parents. Some genes cause puberty to happen at the later range of normal and some earlier.
Because of this it's hard to predict a human's size bc you have to look at both their nutrition/general lifestyle whilst they're growing up, as well as the genes which code for onset of puberty.
A lot of size differences in body features is due to a complicated combination of all of those traits/genes, and not just 1 gene. There's no size gene that's passed down.
Another example is hair colour, it's often coded in an additive way in the human body and furred mammals. There's several pigments in our DNA, but a lot of different genes which can produce the same pigment. Some hair/coat colours are produced by the expression of the genes for 1 pigment, but others are by the expression of genes for 2-3 different pigments. (Humans don't have too much pigments though, but we have lots of genes to produce the same pigment) Some of those genes may be recessive or dominant. So hair/fur colour is actually quite a huge grab bag and there's no gene for hair colour that's really passed down.
I think if you want to do further reading on this topic it's better to study known genes and what they code for, rather than study physical differences and try to guess how the genes that influence them are passed down. The former approach will allow you to see more clearly how genes/certain traits, are similar across lineages.
There's nothing here!