x= c(0,1,0,0,0,1,1,0) # 0=delfin, 1=leonmarino 
y=c(0,0,0,1,1,1,1,0) #0=macho, 1=hembra 
z=table(x,y)
z 
rownames(z)= c("delfin","leonmarino")
colnames(z)=c("macho","hembra")
z