Why Func instead of Predicate?

This is just a curiosity question I was wondering if anyone had a good answer to:

In the .NET Framework Class Library we have for example these two methods:

public static IQueryable<TSource> Where<TSource>(
    this IQueryable<TSource> source,
    Expression<Func<TSource, bool>> predicate
)

public static IEnumerable<TSource> Where<TSource>(
    this IEnumerable<TSource> source,
    Func<TSource, bool> predicate
)

Why do they use Func<TSource, bool> instead of Predicate<TSource>? Seems like the Predicate<TSource> is only used by List<T> and Array<T>, while Func<TSource, bool> is used by pretty much all Queryable and Enumerable methods and extension methods… what’s up with that?