Why do some insurance companies hire actuaries AND data scientists and what exactly is the separation of responsibilities? (X-POST Actuary)

I started thinking about this after I saw that Liberty Mutual Insurance company, hosted a "data science" competition on Kaggle ( Liberty Mutual Group - Fire Peril Loss Cost Predict expected fire losses for insurance policies). As I looked around past competitions I noticed that a there were a few competitions that focused exclusively on things that actuaries traditionally do. They all fell into the specialties of p&c, consulting, and health.

When I looked around the careers sections of some of these companies and other insurance companies, I noticed that some of them hired data scientists and some of them didn't. Of the ones that hired data scientists some companies placed them in the Actuarial/Research department and some place them in the software development/IT department.

So I'm wondering, why would an insurance company hire actuaries and data scientists? What's the rational behind putting them in different departments? What exactly is the separation of responsibilities like?

I also asked this question on r/actuary.