《那些古怪又讓人憂心的問題》第72期:自體繁殖(6)

Charles had an inbreeding coefficient of0.254, making him slightly more inbred than a child of two siblings (0.250). Hesuffered from extensive physical and emotional disabilities, and was a strange(and largely ineffective) king. In one incident, he reportedly ordered that thecorpses of his relatives be dug up so he could look at them. His inability tobear children marked the end of that royal bloodline.

卡洛斯的近交係數爲0.254，僅僅比兄妹結婚的近交係數（0.250）高一些。他有重度身體和情緒殘疾，是一個極其古怪（也極其無能）的國王。根據史料記載，有一次他要求把他的親屬的屍體都挖出來，這樣他就能一直看着他們。由於他沒有生育能力，因而皇族血統到他這一任也就終結了。

Self-fertilization is a risky strategy,which is why sex is so popular among large and complex organisms.3 There areoccasionally complex animals that reproduce asexually,4 but this behavior isrelatively rare. It typically appears in environments where it's difficult toreproduce sexually, whether due to resource scarcity, population isolation . ..

所以說自體繁殖是個很危險的策略，這也是爲什麼在稍大、稍複雜的種羣中，性是如此普遍的原因。3雖然有時一些高等生物也會無性繁殖，4但這種行爲是相對罕見的。這種情況通常發生在異性繁殖非常困難的環境中，困難的原因包括資源稀缺、種羣分散……

Life finds a way.

生命會找到出路

. . . or overconfident theme parkoperators.

……或者某個過於自信的主題公園管理員。

1 Because 1 is the multiplicative identity.

1．因爲1是乘法恆等元。

2 Some forms of SMA are actually caused bya defect in two genes, so in practice the statistical picture is a little morecomplicated.

2．一些種類的脊髓性肌肉萎縮症是由兩個基因導致的缺陷造成的，所以實際上患上這種疾病的機率有些不太好計算。

3 Well, one of the reasons.

3．好吧，原因之一。

4 “Tremblay's Salamander” is a hybridspecies of salamander that reproduces exclusively by self-fertilizing. Thesesalamanders are an all-female species, and - strangely - have three genomesinstead of two. To breed, they go through a courtship ritual with malesalamanders of related species, then lay self-fertilized eggs. The malesalamander gets nothing out of it; he's simply used to stimulate egg-laying.

4．“特倫布利蠑螈”是一種混種蠑螈，繁殖完全靠自體繁殖完成。進行繁殖的都是雌性蠑螈，讓人驚訝的是它們有三組而不是兩組基因組。在繁殖期間，雌性蠑螈和雄性蠑螈會進行求愛儀式，然後產下自體受精的卵。雄性蠑螈在這一過程中什麼都不會得到，它們的作用只是用來促進產卵。