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
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.
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)。
(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。
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。
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。