Traction.
It’s why they put spikes on track shoes,
and interestingly, very similar little split lines on new all-weather tires (for which I paid about $550 at Firestone :>)
After all, if one were to break a man and an ape down to their constituent parts he would soon observe that both consist of the same quantum particles and fields that make up rocks and galaxies. And yet that would tell the investigator little about either man or ape, because along the way of breaking them down - both would move from being alive to being dead. And of course neither rock nor galaxy is alive.
Or to put it another way, along the way of breaking the man and ape down, something was removed which was not physical at all.
So whether one looks at quantum field theory and gasps that all physical things whether alive or dead have it in common – or whether one looks at physical structures and gasps that all physical things whether alive or dead have geometry in common – or whether one looks at living man and ape and gasps that they both have ridge detail on their feet and hands – the truly amazing part is that life is not physical at all. The rest is just coincidence among things which evoke a physical description.
As Einstein once said "Coincidence is God's way of remaining anonymous."
Truth is hidden in plain view but without "ears to hear" and "eyes to see" man cannot perceive it.
Where [is] the wise? where [is] the scribe? where [is] the disputer of this world? hath not God made foolish the wisdom of this world?
For after that in the wisdom of God the world by wisdom knew not God, it pleased God by the foolishness of preaching to save them that believe.
For the Jews require a sign, and the Greeks seek after wisdom: But we preach Christ crucified, unto the Jews a stumblingblock, and unto the Greeks foolishness; But unto them which are called, both Jews and Greeks, Christ the power of God, and the wisdom of God.
Because the foolishness of God is wiser than men; and the weakness of God is stronger than men. - I Corinthians 1:18-25