The elephant has 56 chromosomes, and the mammoth has 58. The donkey has 62 chromosomes and the horse has 64, yet horses and donkeys can mate to produce mules and hinnies. Creak communicated the good news at once to Yasmilov, who promptly set to work trying to fuse the nuclei from the mammoth ova, in their new cytoplasm, with sperm from an Asian elephant bull. As Creak points out, this delicate work requires highly skilled technicians. Creak expressed concern about the state of experimental science in general.
Some scientists like to proceed in small, carefully thought-out steps.
I see science as high adventure, with enormous risks. Of course, the rewards are commensurately high if the gamble comes off. Yasmilov attempted to artificially inseminate the mammoth ova with elephant sperm over 60 times before achieving fusion in eight samples. The resulting cell clusters were implanted in the wombs of Indian elephant cows. The timing of implantation is tricky, as the elephant cow must be in heat and proceed directly to the pregnant state after the embryo is implanted.