why the difference in these chicks?

[pamsorpies]

I have 10 buff orpington chicks that will be 3 weeks old this coming Wed. 7 have long feathered wings and 1.5 to 2 inch tail feathers, 3 have short wings and no tail feathers.
What's the difference? I'm new to this so thank you

 

[Northern nurse]

We'll, not that I know much but I have read that roo's can be slower to grow in their tail feathers. Do you know if these are supposed to be all girls or are they from a straight run?

 

[pamsorpies]

They are straight run. I had read the same thing but still not sure. Thank you

 

[WilhelminaD]

Yeah, likely they're cockerels. Mine were much slower to grow than my pullets.