You haven't really answered why though.
Laws are designed by and for humans so it's not a great metric for value. In fact laws are more often designed by and for a paricular society so it's an even worse metric than first thought.
For example, 100 years ago in the west the life of a straight white man would have been considered more valuable than that of a women, homosexual or black man (and you could argue that this is still the case in many societies across the world) using that metric. But I'd hope must of us would argue that that was/is wrong.
So no, laws aren't a good indicator of the value of a life.
Neither is using the position of a species on the food chain to value their lives. Phytoplankton and plants are near the bottom of the marine and terrestrial food chains but without them everything dies.
To me value is all about contribution. The human species, as a whole, takes far more from the planet than it contributes to it, but at the same time has the potential to innovate and create beyond anything else. Plants and animals may not be able to invent like us but they ensure the world remains a habitable and pleasant place for us to live.
Our greater intelligence means we have a greater responsibility and until we use that for the benefit of the planet instead of ourselves I will always disagree with the notion that a human life is more valuable than an animal life, at least at a species level.