Now, a study shows that at least one aspect of life continues: Genes remain turned on days after animals die.
The team measured which of these genes were functioning in tissues from recently deceased mice and zebrafish, tracking changes for 4 days in the fish and 2 days in the rodents.
At first, the researchers assumed that genes would shut down shortly after death, like the parts of a car that has run out of gas.
Although most of these genes upped their activity in the first 24 hours after the animals expired and then tapered off, in the fish some genes remained active 4 days after death.
“What’s jaw-dropping is that developmental genes are turned on after death,” Noble says.
The patterns of gene activity that the researchers observed may represent what happens when the complex network of interacting genes that normally keeps an organism functioning unwinds.
Some genes may turn on, for example, because other genes that normally help kept them silent have shut off.