LBT237-240嘉芸

LBT237-240嘉芸

撰寫人：9580023 張嘉芸

The pages：237 ~ 240

Although it is quite conceivable that behavioral propensities yield more readily to selection pressures and are, perhaps, also more easily affected by genetically conditioned variations, thus changing at a more rapid rate than skeletal structure, for instance, we must still remember that all evolutionary changes affect animals as a whole. Entire patterns of life, so to speak, are altered but at each time-slice there is, necessarily, full integration and mutually adaptive interaction of all of the animal’s features; it is the condition for viability and successful continuation of the species. This consideration has an important consequence for reasonable expectations of the phylogenetic history of one specific trait, such as human language. Individual traits of an extant species can never have a continuous history because they do not evolve independently from the rest of the animal. Thus we see that there is every reason to believe that animal communication is a discontinuous affair and that logical commonalities among communication systems are not necessarily indicators of a common biological

origin.

FIG. 6.3. Schema of the evolution of the Hominoidea.

(c) The Sharing of Traits. These assertions are not contradicted by the wealth of evidence that some sort of symbolic behavior can be demonstrated in a wide variety of animals, that the communication of affect is very common, or that territoriality, protection of the young, or maternal behavior is frequently accompanied by vocalizations. It is true that animals share certain traits; it follows directly from the tree-like relationship between species. Notice, however, that the phylogenetic relationship between species cannot, in most cases, be represented by a single, unique tree-diagram that accounts for absolutely all of the commonalities and all of the specific differences. A tree that characterizes the relationship of skeletal structures of certain species fairly well, may differ in some (usually small) respect from a tree that characterizes the relationship between given protein structures (Goodman, 1963).

FIG. 6.4. Tree diagrams or descent may be represented as Euler-Venn diagrams.

(a) is a representation of Fig. 6.3 (Chapter Six). Individual traits of behavior are often distributed over species in such a complex way that tree diagrams cannot be used at all, and set diagrams can only be used at the risk of oversimplification.

(b) is a hypothetical representation of vertebrate communication systems that could not be shown by a single tree.

This is due to a number of circumstances; for example, certain aspects of life do not allow of as many (or any) variations as others; or there may be only one or very few possible biochemical solutions to a given problem posed by the environment so that a similar condition comes about more than once throughout the animal kingdom; or certain features are lost or added by individual species.

Tree-diagrams may be converted to Euler-Venn diagrams such as shown in Fig. 6.4 where (a) is a representation of the tree in Fig. 6.3 and (b) is a hypothetical diagram that might show some of the relationships of individual traits, some of them pertinent to human language. Each of the rings may be labelled; the labels tend to become more abstract as we move from center to periphery. The inner circles represent phenomena that can be directly observed on present-day animals. Each encompassing ring is a postulation lf a more general form of the contemporary phenomenon. If an outer ring be vocalizations, this will not be a homogeneous set of behaviors but a collection of types of behavior each of which is today a highly specialized biological function. Thus we see once more that the sharing of traits does not necessarily reveal the history or nature of any specific development.

Ⅱ. ARE BIOLOGICAL THEORIES OF LANGUAGE DEVELOPMENT COMPATIBLE WITH CONCEPTS OF GENETICS?

Before we proceed with further speculations about the biological origins of language, we must pause to ask whether present-day concepts of genetics and development are compatible with the facts known about language.

(1) Genes and Ontogenetic Development

The first problem is posed by what is known about the specific action of genes. DNA molecules, the biochemical correlates of genes. Probably do no more than control the protein synthesis within the cell. The undifferentiated cells of higher animals have, however, a very large repertoire of different “instructions” for different types of synthesis, and these come into play at various stages of development (Beermann, 1963). The puzzle now is: if the inherited genetic information concerns essentially nothing but intracellular events, how could something like the capacity for language have a genetic foundation? The phenomenon is, after all, entirely supracellular or even more general, namely an interrelation of activities of complex assemblies of cells.

This puzzle is, of course, not peculiar to the problems of the genetic basis of language but to the relationship between genic action and the inheritance of traits in general. Although we can only speculate on this point, our speculations with regard to language are no more daring than with regard to most other structural or functional features.

Animals develop as an integrated whole including structure, function and behavioral capacities; the latter two are not secondary installations after embryogenesis. Therefore, it may not be too far-fetched if we say a word about development in general, the assumed role of genes in ontogenetic and phylogenetic development, and how these concepts apply to the development of language.

It is common knowledge that the first cells formed during mammalian ontogenesis have embryological equipotentiality. Up to the stage called gastrulation, the cell aggregate may be divided artificially in two, and each remaining half will develop into a well-shaped individual. But soon some of the cells in the gastrula become specialized, a division of labor has set in among the cells which soon deprives them of the capacity to change their own structure and function back to the original state. A certain spot in the gastrula begins to act on surrounding cells, thus inducing fast cell division, local expansion, folding, invagination, tubular structures, inclusions, etc. We speak of an organizer that has developed and which has caused some differentiation in its neighborhood. Organizer after organizer develops. At later stages entire tissues or organs serve as organizers or inducers for other tissues and organs.

【翻譯】

雖然生物的習性更快地產生淘汰壓力而且或許也是更容易地受遺傳學基因方面地控制變因的影響都是相當可以想像的，因此改變的比率比骨骼構造更快速的話，舉個例子來說，我們還是必須記得整體演化的改變影響著動物的一生。整個生命的模試可以說是被改變，但在每一個時間片段裡必定充滿著整合性和所有動物的特徵彼此適應的交互影響；這就是能生存下來和成功地延續物種的條件。這個考慮對一個特別的特徵在動植物種類史的合理的預期有一個重要的結果，例如人類的語言。現存物種的個體特徵可能永遠都沒有延續的歷史因為他們無法從剩餘的動物中獨立地演化。因此我們發現有每個理由可相信動物的溝通是一個非延續的事件並且相信在溝通系統中有邏輯的共性不一定是共同生物源的指標。

圖. 6.3. Hominoidea的演化概要輪廓圖 (c)物種的分享 這些言明不會因豐富的證據被反駁，證據就是象徵性行為的一些類型在廣泛的動物異種性中可以被顯示出來，溝通的影響是非常普遍的或地盤性、保護幼小或母性的行為屢次都會伴隨著發聲。動物會共享某種特徵是真實的；它在物種之間直接跟隨著來自像樹狀一樣的關係。然而要注意的是在大部分的實例中物種之間的動植物種類關係不能藉由單一、獨特的樹狀圖被表現出來，樹狀圖是對完全地所有共性和所有物種差異的說明解釋。描繪所知道的某種物種的骨骼構造關係的特性的樹狀圖在一些(通常很小)的關係方面上，是不同於描繪已知的蛋白質構造的特性的樹狀圖(Goodman, 1963)。

圖. 6.4.三個曲線圖或下降遺傳以Euler-Venn圖被表現出來

(a) 是圖6.3 (第六章節) 的表示法。行為的個體特徵經常是用這樣一個複雜方式被分佈在物種裡，這個方式就是,樹狀圖根本無法被使用,，並且使曲線圖可能只被使用在過度單純化的事物的風險上。

(b) 是一個不能由單一世系圖顯示的脊椎動物的溝通系統的假定表示法。

這是由於環境的數量上的優勢；例如，生命的某些方面不允許和其他一樣有許多(或任何) 變異；或者也許只有一個或少量對一個由環境引起的已知問題的可能生物化學的解決辦法，以便遍佈在動物王國中一個相似的情況發生多於一次；或者某種特點被個體種類丟失或增加。

樹狀圖也許被轉換成Euler-Venn 圖例如被顯示在圖6.4 在圖6.3 的地方(a) 是世系圖的表示法並且(b) 是可能顯示一些個體特徵關係的假定圖，它們之中有些和人類的語言有關。每個圓環也許被標記；當我們從中心到周圍移動時標籤傾向於變得更加抽象。內圈代表著可以直接觀察當代動物的現象。各個繞圈的圓環是一個假定lf 同時期現象的更加一般的形式。如果一個外圍圓環是發聲的樣子，這不會是行為的同性質集合而是行為類型的收集物且每個行為是現今一個高度專業生物的作用。因此我們看見更多特徵的共享不一定顯露任一明確發展的歷史或本質。

Ⅱ.語言發展的生物理論是與遺傳學的概念相兼容嗎?

在我們對語言的生物起源進行更進一步的推測之前, 我們必須停下來問是否遺傳學和發展的當代概念是與已知關於語言的事實相兼容。

(1) 基因和個體發育的發展

第一個問題由所知關於基因的明確行動被提出來討論。DNA分子是基因的生物化學相關物。大概做出僅僅控制在細胞之內的蛋白質聚合物。更高階層動物的無差別的細胞然而為了不同的合成類型有一個不同"指示" 的非常大的指令系統並且這些在發展各式階段中進入比賽(Beermann, 1963)。現在難題是：如果遺傳的基因資訊本質上只與細胞內的事件有關，那某事像語言能力是如何有一個基因基礎呢？現象是終究完全超細胞的或甚至更加一般的，也就是細胞複雜的集合的活動的相互關係。

這個難題對語言的基因根據的問題當然不是奇怪特殊的，但對遺傳因子的行動和特徵遺傳之間的關聯性就是了。雖然我們能只在這點上做推測，但我們關於語言的猜想沒有比關於多數其它結構或功能特點更大膽了。

動物發展出像一整合的全部包括結構、作用和關於行為的能力；後面兩者不是次要裝置在胚胎形成以後。因此，它不能是太牽強的如果我們說一個詞關於發展一般而言，基因的擔任的角色在個體發育和種系發生的發展，並且這些概念如何適用於語言的發展。

在哺乳動物的個體發育期間第一細胞形成有胚胎學等勢是平常普通的常識。直到原腸胚形成的階段，細胞集合體也許人工地被劃分成二個，並且各剩下的一半將顯現出完整形狀的個體。但一些細胞在原腸胚很快成為專門的，工作的分配已經設置在細胞之中，細胞很快剝奪他們自己的能力改變他們自己的結構和作用回到原始的狀態。在原腸胚裡某一斑點開始在周圍的細胞行動，因此導致快速的細胞分裂、地方擴展、可摺疊、反折處、管狀結構、胞吞等。我們談到的組織者已經顯現並且在它的鄰近地方導致一些分化。組織者在組織者發展以後。在後來的階段對於其它組織和器官整個組織或器官可作為組織者或誘導者。