Resources for Communication Problems

Monday, February 25, 2008



撰寫人:9580012 謝侑倫

The pages243 ~ 245

There is a wealth of data to which the allometric formula has been successfully applied, including measurements of length, volume, weight, and chemical proportions (Needham, 1964) during development. We are therefore, dealing with something that may be fundamental to the growth process itself, and this is not irrelevant to the development of functions and capacities. As tissues grow and differentiate, they serve immediately a physiological function. The functions themselves grow and differentiate to the measure of tissue growth and differentiation, and, therefore, growth laws that hold for tissues may have their parallels with respect to function. Unfortunately, quantification and mathematical treatment is much more difficult in this respect, and we must, therefore, be satisfied with the somewhat vague conclusion that the regularity in the emergence of behavior is related directly or indirectly to the lawfulness of growth and physical development.

It is interesting to note that the allometric formula also describes a number of quantitative relationships between species. Instead of taking pairs of measurements on growing individuals of different species. By this method it can be shown that certain relations of magnitudes obey a simple law that is related to the fundamental phenomena of general growth. Thus, the relation of cerebro-cortical surface in rodents to the weight of their body (Bok, 1959), or the volume of the neocortex to the volume of the brain in all primates(v.Bonin,1950) can be expressed by simple mathematical formulae. The existence of regularities of this kind should warn us not to attach too great importance to certain structural differences found between species, because they may not necessarily be signs of specific adaptations to a unique condition but simply result from changes in over-all size of the animal. As an example we may cite the extent of folding of man’s cerebral cortex or the size of his corpus callosum or certain transcortical fiber connection, or the size and extent of association cortex, which may be the consequence of growth laws expressed by formulae such as the allometric one instead of being a unique specialization for intelligence or language(see also Sholl, 1948). One of these interpretations does not automatically exclude the other but together they point to the complexity of evolutionary events.

The purpose of these excursions was to show that physiological processes are ultimately dependent upon certain structural features of the organism, even though these features may not be obvious upon superficial inspection. This is particularly so in cases where the dependence is upon internal organs or upon the molecular constitution of component tissues and cells. The peculiarities of structure, on the other hand, are entirely a function of developmental growthand growth is to be described by temporal and directional (spatial) parameters. The great regularity of developmental histories within species indicates that time and direction of grpwth must be controlled by factors that may be traced back to intracellular activities which are under the control of genes and their influence upon the elaboration of certain enzymes at certain times. The route through which genes affect the over-all patterns of structure and function is their action upon and direction of ontogenesis, especially the prolonging and shortening of growth and differentiation periods; genetic variations between species should, therefore, find their immediate and most dramatic expressions in embryological and postnatal developmental histories. Such an idea is not new. It was proposed(sometimes together with far-reaching and even unwarranted by Goldschmidt (1938) and (1952).

Consideration of this type show that it is possible to talk about language in connection with genetics without having to make shaky assumptions about“genes for language.”It is true that we do not know what the direct relationships are between man’s complement of genes and his mode of communication; we merely wish to outline the theoretical possibilities for relation the two. It is in this vein that the observations on twins and pedigrees, cited below, are to be interpreted (cf. Georgacopoulos, 1954; Grothkopp, 1934; Howie et al., 1961). There is in fact, one line of evidence that makes the general line of argument used here even more plausible. If gene-variations are the raw materials for speciation (played upon by selection ) and this is reflected in inter-species differences in ontogenetic history, then a highly species-specific feature such as the capacity for language might well be involved in some fashion in species-specific developmental peculiarities. Marked inter-specific differences in maturational histories are well-documented and reported upon by Altman and Dittmer (1962), and the material on primates is beautifully reviewed by Schultz(1956).

In Chapter Four we have pointed out that man’s history si markedly different from that of other primates. The human neonate is considerably more immature at birth than our closest of kin, with a concomitant prolongation of differentiation periods and increased susceptibility for various factors to impinge upon the direction of further development. The acquisition of language plays a definite part in this developmental history, its emergence occupying a fixed position within the array of developmental milestones, and there are definite indications that its development is contingent upon a certain aspect of what might be called.


有一個異速生長的公式在發展期間已經被成功使用大量數據, 包括長度的尺寸,體積,重量和化學比例(尼德姆,1964)。因此,我們處理的是一些發展的基礎,並且這與功能和能力的發展不相干。當組織增長並且有差異時,他們立即有一個生理的功能。功能本身成長並且使與連串發展和區別的措施有差異, 因此,組織發展的規則可能與他們有相似的作用。不幸地,定量和數學處理在這方面更難,因此,我們必須, 對在行為的出現過程中有點含糊的結論的規律性直接或間接發展的合法和物理發展有關的滿意。

注意到異速生長的公式也描述許多種類之間的定量關係是有趣的。不是花費測量法在不同種類的個人發展上。以這種方法可以被顯示某些重要的關係遵守一條和基本發展的現象有關的簡單的規則。因此,大腦皮層的表面在嚙齒動物與他們的身體的重量有關(博克,1959) ,或者靈長類的新皮質體積佔大腦的全部體積(v.Bonin1950)可以藉由簡單的數學公式表示出來。這種的規律性的存在應該警告我們不要給予在種類之間的某些架構差異有太大的重視, 因為他們對一種獨特的條件不一定能是具體的適應跡象,但是僅僅起因於在動物的全部大小的變化。作為一個例子我們可能引用人的大腦皮層或者他的硬體或者相關通過皮層的纖維連接的大小,或者社會皮層的尺寸和範圍, 那個是可以藉由異速生長公式作為發展規則的結果,而不是作為智力或者語言(也看Sholl1948)的獨特專業化發展規則的結果。這些說明的其中之一並不自動排除另一個,但是他們指出進化事件的複雜性。

這些移動的目的顯示生理的過程最後倚賴生物體的某種構造,即使這些特徵可能不能明顯的顯示外表的檢查。這是特別的事件倚賴在內部器官上或者在組成組織和細胞的分子結構上。另一方面,此架構的特點完全是一個發展的功能; 並且藉由暫時和方向性(空間)參數去描述發展。在種類內發展歷史的規律性指出時間和空間的發展必須被一些因素控制,那是被追溯到細胞內的活動,在某些時候基因的控制和他們的某些酵素製作的影響。基因影響全部的結構模式和功能的路線是他們行動和個體發生的方向,尤其發展和不同時期的延長和縮短;因此,種類間的基因變化應該找出他們直接和最引人注目的的表示在胚台學上和產後發展的歷史。這樣的想法不新。戈德施米特提議這樣的想法是深遠的而且即使是無保證的( 1938 ) ( 1952 ) .


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