21. This is a creepy study that whispers things like superior race and selective breeding . 22. Cloning is the most widely proposed method, although selective breeding has also been proposed. 23. In 1987, selective breeding began, aiming to concentrate the quagga genes in successive generations. 24. In line with this, selective breeding of Karachay horses ensued. 25. Using selective breeding and other techniques, they also are working to domesticate wild perennials. 26. Their current small stature is a function of selective breeding . 27. Through selective breeding , they have become well adapted to the soil in northern Estonia. 28. The company has its own selective breeding programmes integrated with quality control and production. 29. Through selective breeding , the doctor has put together the perfect bull for creating art, 30. Selective breeding may be required to produce homozygous knockout animals.