CREATE TABLE table_204_358 (id DECIMAL, "species" TEXT, "common name" TEXT, "ncbi accession #" TEXT, "ncbi name" TEXT, "length" TEXT, "sequence identity" TEXT, "sequence similarity" TEXT, "years since divergence from human  ( mya ) " DECIMAL)

how many years has it been since the cow has diverged from human ?
SELECT "years since divergence from human (mya)" FROM table_204_358 WHERE "common name" = 'cow'
SELECT "years since divergence from human (mya)" FROM "table_204_358" WHERE "common name" = 'cow'