When the universe was younger, the fraction of spiral galaxies was much higher than now

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The question is very interesting and very relevant to the studies we do. Understanding why galaxies have the shape they do and how their structure is related to their formation processes and evolution is a fundamental part of my research. It is important that you know that the fact that our galaxy is spiral is not a rarity, there are many that have a very similar shape. In fact, most galaxies are spirals. Properties such as its mass, its environment or the age of the universe influence whether that number is higher or lower. We classify galaxies into two types: elliptical and spiral. When the universe was younger, the fraction of spiral galaxies was much greater than now that the universe is older since galaxies are transformed into ellipticals by internal processes that we call secular. Also, in general, the smaller the galaxies, the more likely they are to be spirals rather than ellipticals.

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