until now

But until now, no one had found those earlier forms in the fossil record.

"The most surprising finding here isn't that male and female mice sleep differently. It's that no one has thoroughly shown this until now," said Rowe.

But until now, we have not been able to capture the molecular signals that unleash memory formation.

Up until now, efforts to get these ideas off the ground have been limited by money — buying one small building in L.A. can cost millions.

Although many attempts have been made to convert captured CO2 into useful products, until now most researchers have only shown the ability to produce carbon monoxide.