Or HaChaim on Genesis 7:23/אור החיים על בראשית ז׳:כ״ג

1 וימח את כל היקום. He dissolved all life. Not only did all living creatures of the earth (dry land) die, as pointed out in verse 21, but their remains dissolved completely due to the heat of the waters. No trace of them was left. This verse also enables us to understand the comment of Rabbi Ami in Eyruvin 18 on Psalms 139,5: אחור וקדם צרתני, ותשת עלי כפכה, "You have made me before and behind; You lay Your hand upon me." Rabbi Ami understood this to mean that Adam was created at the end of the whole process of creation whereas the word קדם refers to "prior to the curse." Rabbi Ami meant that man disintegrated before the curse, i.e. before all the animals' bodies dissolved. He referred to man dying ahead of the animals during the deluge. Who needed Rabbi Ami to tell us something that the Torah has already spelled out in 7,23? Actually, when you look at verse 21 you notice that the death of the creatures is reported in the reverse order, i.e. first the animals, then the human beings. According to our interpretation there is no contradiction here. Whereas verse 21 discusses the timing of the deaths, verse 23 discusses the dissolution of the remains of the dead creatures. Man's remains dissolved first though he had died last.