MPDの拡張版であるTime Sensitive Maximization of Phylogenetic Diversity(Time-PD)とStrict Time Sensitive Maximization of Phylogenetic Diversity(s-Time-PD)が提案され、NP-hardであることが示された。
"Phylogenetic Diversity (PD) is a measure of the overall biodiversity."
"MPD is polynomial-time solvable by a greedy algorithm."
"These problems have much in common with machine scheduling problems."