These newly discovered rules allow scientists to better predict which dinosaurs could also fly. The new data could resolve some long-standing debates in paleontology about whether flight evolved in dinosaurs on more than one occasion. By examining the wing feathers of 346 different species of birds From museums around the world, Field Museum of Natural History ornithologist Yusef Kayat discovered an interesting trend: from the smallest hummingbirds to the fiercest eagles, all flying birds had between 9 and 11 asymmetric flight feathers called the "primary feather." Or the basic ones. But the number of basic feathers in flightless birds varies greatly, and the “emu” lacks them completely, while some others think that penguins have 40 feathers, according to a scientific study published in the scientific journal “Science Alert”. Kiat says “It's really surprising that with so many flight patterns that we can find in modern birds, they all share this trait of having between 9 and 11 primary feathers, and I was surprised that no one seems to have found this before.” He added: “Possible publications include Archeopteryx (considered one of the oldest bird-like animals). While there is controversy about the true relationship between Archeopteryx and birds, small four-winged dinosaurs called Microraptors also had these features.” Although it is not directly related to birds at all.”