The rock shown here, with sediment just visible to the naked eye, is a:

Metamorphic-result from pre-existing rocks that have been altered physically and/or chemically without melting. The agents of these changes include intense heat and pressure and/or chemical actions of hot fluids

Ifound this on google “according to the findings, a foramen magnum positioned toward the base of the skull is found not only in humans, but in other habitually bipedal mammals as well.” i hope this you for what your looking for