  Given a set $S$ of $n$ points in the plane, we consider the problem of
answering range selection queries on $S$: that is, given an arbitrary $x$-range
$Q$ and an integer $k > 0$, return the $k$-th smallest $y$-coordinate from the
set of points that have $x$-coordinates in $Q$. We present a linear space data
structure that maintains a dynamic set of $n$ points in the plane with real
coordinates, and supports range selection queries in $O((\lg n / \lg \lg n)^2)$
time, as well as insertions and deletions in $O((\lg n / \lg \lg n)^2)$
amortized time. The space usage of this data structure is an $\Theta(\lg n /
\lg \lg n)$ factor improvement over the previous best result, while maintaining
asymptotically matching query and update times. We also present a succinct data
structure that supports range selection queries on a dynamic array of $n$
values drawn from a bounded universe.
