If you're new to yoga, you might be surprised that yoga is practiced barefoot and often involves focusing on your feet. After all, since we were babies our feet have been shoved into socks and shoes, and now you're in a yoga class grabbing your toes with your hands, interlacing your fingers between your toes, and getting acquainted with your feet. Why?
There are a number of reasons. In yoga, we work from the foundation up. This means that if you're doing a standing pose, you start not by jumping right into it, but by looking at your feet and building a stable foundation. You ground down through all four corners of both feet, you spread the toes. For all standing yoga poses, start with the feet. You'll be surprised at how it can transform your postures.
As for spreading your toes- just as you have muscles in your hands to help your fingers to spread, you have muscles in your feet to help spread your toes. When our feet are shoved into tight shoes, our toes get crunched and we lose the muscles that help our toes to spread. A number of bad things can occur when our feet are squished from shoes- plantar fasciitis, poor circulation, fallen arches, Morton's neuroma, etc.
The good news is that it's never too late to retrain those muscles. You can start by standing tall, lifting the toes, spreading them as wide as you can, and setting them down. You can always interlace your fingers between the toes.