Does " they ended up doing" refer to "they finally did doing"?

Context:

By the time Szyf arrived at McGill in the late 1980s, he had become an expert in the mechanics of epigenetic change. But until meeting Meaney, he had never heard anyone suggest that such changes could occur in the brain, simply due to maternal care. "It sounded like voodoo at first," Szyf admits. "For a molecular biologist, anything that didn't have a clear molecular pathway was not serious science. But the longer we talked,the more I realized that maternal care just might be capable of causing changes in DNA methylation, as crazy as that sounded. So Michael and I decided we'd have to do the experiment to find out."
Actually, they ended up doing a series of elaborate experiments. With the assistance of postdoctoral researchers, they began by selecting mother rats who were either highly attentive or highly inattentive. Once a pup had grown up into adulthood, the team examined its hippocampus, a brain region essential for regulating the stress response. In the pups of inattentive mothers, they found that genes regulating the production of
glucocorticoid receptors, which regulate sensitivity to stress hormones, were highly methylated; in the pups of conscientious moms, the genes for the glucocorticoid receptors were rarely methylated.