The bechor-offering precedes the maaseroffering because its sanctity begins at birth and it is eaten by the Kohanim. The maaser-offering precedes bird [offerings] because it is slaughtered and it has [parts which are] most holy — its blood and sacrificial parts.

Bird offerings precede minchah-offerings because they are in the category of blood [offerings]. A sinner’s minchah-offering precedes a voluntary minchah-offering because it is brought for a sin. A bird chatas precedes a bird olah; and so too with its consecration.