Why do cactus have thorns?

[arydberg]

TL;DR Summary

A different explanation for thorns on plants.

I know the party line. That the thorns prevent animals from eating the plant. The problem is I do not believe it. Deer are known for eating roses and goats can eat thistle like you would not believe. I think the thorns serve an electrical function and carry the tiny currents that flow from the sky into the plant. Here is a link to a book on Atmospherick electricity.

http://www.electrocultureandmagneto...trom_electroculture_agriculture_111p_1904.pdf

 

[jim mcnamara]

Natural selection does not alter genetic frequencies to fit the situation. Arid species like Acacia, Ferrocactus, Euphorbia are completely unrelated and arose on different continents. All have thorns. The thorns are derived from different tissues.

You are assigning meaning, direction and/or intent to the process of evolution. There is none.

The citation you gave is, to be polite, not correct, as is your understanding of Natural Selection. The book was published in 1904. I am not going to debunk it.