Long ago, all sex cells on Earth were the same size. It was the age of the isogametes. Maybe not exactly the same… Some were a little bigger than others. The embryo from the big ones had some advatages – they had a larger supply of food. The little ones immediately developed a strategy, otherwise they disappeared. The strategy was elementary: to merge with the bigger ones, to avoid sexual encounter with those like them. But the big ones weren’t always available. They had to be searched. This is how the little ones became more mobile than the big ones who, being desired, had no reason to move. The next step was logical: cells that produced smaller gametes, with more “matter” available, began to produce many. It’s simple, isn’t it? Small, but many! The others were few but big!
If you have ever wondered what the essence of masculinity or femininity is, at the elementary level, this is the answer: individuals with large sex cells are called females. Individuals with small sex cells are called males. This is the case everywhere, in the whole live world – plants, animals, people). Female gametes are few and large, so they are precious. They are called eggs. 300 to 400 eggs will be ovulated during a woman’s reproductive lifetime. Male gametes are small and very numerous. They are called spermatozoids. In a single ejaculation a man eliminates ~250 million.
Compare the numbers yourself and draw your own conclusions!