diff --git a/optimizer/box-eater.cpp b/optimizer/box-eater.cpp
index 7a4940c..b6aab37 100644
--- a/optimizer/box-eater.cpp
+++ b/optimizer/box-eater.cpp
@@ -306,7 +306,7 @@ int main() {
 
 		std::vector<Species> Hnxt, Lnxt;
 		for (auto &s : biosphere) {
-			if (s.stable_age <= 15 || s.best_w == best_w) {
+			if (s.stable_age <= 15 * s.best_w / best_w || s.best_w == best_w) {
 				if (s.best_w < best_w || s.age <= 35)
 					Hnxt.push_back(std::move(s));
 				else