# Møller, A. P. (1988). Ejaculate quality, testes size and sperm competition in primates. Journal of Human Evolution, 17(5), 479–488. 

Hylobates_lar<-152.4
Gorilla_gorilla<-c(171,191,48.4,107.9,195.2)
Pan_troglodytes<-c(548,608.8,391.1,258.3,142.9,274.5)
Pan_paniscus<-456.1
Pongo_pygmaeus<-61
Homo_sapiens<-63.5
samples<-lengths(list(Hylobates_lar, Gorilla_gorilla, Pan_troglodytes, Pongo_pygmaeus, Homo_sapiens))

L<-max(samples)
sperm_conc<-matrix(nrow=L,ncol=5)
sperm_conc[1:length(Hylobates_lar),1]<-Hylobates_lar
sperm_conc[1:length(Gorilla_gorilla),2]<-Gorilla_gorilla
sperm_conc[1:length(Pan_troglodytes),3]<-Pan_troglodytes
sperm_conc[1:length(Pongo_pygmaeus),4]<-Pongo_pygmaeus
sperm_conc[1:length(Homo_sapiens),5]<- Homo_sapiens
mean(sperm_conc[,2],na.rm=TRUE)