कोशिका पशु जगत का सबसे पहला आविष्कार थी, और सभी उच्च कोटि के जीव कोशिकीय संरचना से बने हैं और होने भी चाहिए। हमारे ऊतक युगों-युगों पहले बने थे; वे आज भी वैसे ही कायम हैं। हमारे अधिकांश अंग उतने ही पुराने हैं जितने कि कीड़े। ये सभी बहुत पुराने हैं, पहाड़ों से भी पुराने।
The cell was the first invention of the animal kingdom, and all higher animals are and must be cellular in structure. Our tissues were formed ages on ages ago; they have all persisted. Most of our organs are as old as worms. All these are very old, older than the mountains.
The cell was the first invention of the animal kingdom, and all higher animals are and must be cellular in structure. Our tissues were formed ages on ages ago; they have all persisted. Most of our organs are as old as worms. All these are very old, older than the mountains.
मेरे एक मित्र ने इन व्याख्यानों का शीर्षक [मान्वीय उद्गम और भविष्य] पढ़कर कहा: "तुम्हें इंसान की उत्पत्ति के बारे में कुछ नहीं पता, और उसके भविष्य के बारे में तो उससे भी कम पता है।"
One of my friends, reading the title of these lectures [The Whence and Whither of Man] said: "Of man's origin you know nothing, of his future you know less."
One of my friends, reading the title of these lectures [The Whence and Whither of Man] said: "Of man's origin you know nothing, of his future you know less."
वास्तव में, प्रकृति जहाँ नई संरचनाएँ गढ़ने में अद्भुत रूप से रचनात्मक है, वहीं पुरानी संरचनाओं को सहेज कर रखने में उसकी जिद उससे भी कहीं अधिक उल्लेखनीय है। विकास की इस क्रमिक यात्रा में वह कोई प्रयोग एक बार पूरी गहराई से करती है, और फिर वह मुद्दा हमेशा के लिए हल हो जाता है। क्योंकि वह उस प्रयोग को पूरी तरह परखने के लिए हमेशा पर्याप्त समय लेती है। रीढ़ की हड्डी या मस्तिष्क का निर्माण कैसे हो, यह सीखने में युगों लग गए, लेकिन जब वह प्रयोग पूरा हुआ तो उसके पास संतुष्ट होने की पूरी वजह थी, और वह संतुष्ट हुई भी।
Indeed, while Nature is wonderfully inventive of new structures, her conservatism in holding on to old ones is still more remarkable. In the ascending line of development she tries an experiment once exceedingly thorough, and then the question is solved for all time. For she always takes time enough to try the experiment exhaustively. It took ages to find how to build a spinal column or brain, but when the experiment was finished she had reason to be, and was, satisfied.
Indeed, while Nature is wonderfully inventive of new structures, her conservatism in holding on to old ones is still more remarkable. In the ascending line of development she tries an experiment once exceedingly thorough, and then the question is solved for all time. For she always takes time enough to try the experiment exhaustively. It took ages to find how to build a spinal column or brain, but when the experiment was finished she had reason to be, and was, satisfied.