Out in the Wild West during the time of Colonial Expansion, the native people would put their ears to the ground to listen for herds of bison or groups of horses in the area. Why would listening to the ground be more effective than cupping a hand around your ear while standing up on high ground?

The correct answer to this open question is the following.

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Listening to the ground is more effective than cupping a hand around your ear while standing up on high ground because the ground is denser than the air so the sound of a herd can be heard sooner through the ground than through the air.

That is why out in the Wild West during the time of Colonial Expansion, the native people would put their ears to the ground to listen for herds of bison or groups of horses in the area. Although they were no scientists at all, the Native American Indians were wise men and had a special connection with mother nature. The Natives knew how to interpret the vibration of the ground and realized how long the herd was coming from so they could be ready and know what to do.

i'm pretty sure it's spores