雜種(非純種)動物, 點解比較差劣呢?

"混血兒, 外表漂亮, 教人艷羡" ??
個別啦, 夠有d純種人好似北歐一d民族係美人鄉啦.
"標榜純種, 非純種之動物, 身價不及純種, 而且外觀往往亦沒有純種動物般漂亮, "
身價係人定出來既標準, 靚唔靚更加係人為既. 好似d貓臉圓鼻扁為之靚, 所以d繁殖場就搵d最扁既同d最扁既交配, 生出的貓仔一代扁過一代. 好扁既鼻其實對貓呼吸系統係唔好既, 好容易病, 而且純種貓因為"近親交配"得太厲害, 抵抗力差, 一旦放到野外, 簡直不能照顧自己, 我真係覺得純種動物其實係"殘廢", 而唔係"矜貴". 比著我, 投咁多心機落去培殖一個純種, 梗係收反你貴d架啦, 咁隻動物身價咪高囉, 貴但唔一定代表佢係"優越"d.
我係應為雜種係優越的, 基於一個叫混種優勢hybrid vigor的理論, 可能答到你心中既難題.
http://zh.wikipedia.org/w/index.php?title=%E6%B7%B7%E7%A8%AE%E7%8B%97&variant=zh-hk
混種優勢
根據混種優勢(Heterosis)的說法，混種狗的基因差異較大，令牠們較純種狗更為健康。一些混種狗的確可免受遺傳基因病侵擾，皆因有害的基因在繁殖過程中被剔除，例如德國牧羊犬常會出現髖臼發育異常，但德國牧羊的混種後代一般不會有此病癥。

actually i think that pure-blood and hybrid animals are just the same
maybe people think that pure-blood animals have the pure pedigree of the family
so they are better
this is just psychological effect
some hybrids are very strong and people even help them to produce offsprings
then this hybrid become pure-blood again
so i think pure-blood and hybrid are not very different