GREAT STEPS IN ORGANIC EVOLUTION 891 



as in its own way a notable theatre of plant-evolution? And with 

 this, of course, has to be considered the corresponding fauna, 

 whether vegetarian, as from reindeer to hairy mammoth, or carni- 

 vores, so often protected by rich fur. And with these, too, the 

 seal-tribes in the widest sense, so plainly carnivores, which have 

 found their way to ampler food-supplies, and have so well developed 

 their protection against icy waters by not only their twofold coat 

 of fur, but a fat-layer below. So, too, must not even the ancestors 

 of the various whale-tribes have thus by cold and hunger been both 

 urged and tempted out to sea ? Again, see how specialised and highly 

 developed are the sea-birds of our coldward northern shores and 

 cliffs — and, in their own way yet more, the amazing penguins of the 

 Antarctic? Does it not seem, then, as if — beyond temperate regions 

 with their comparatively moderate and so far equable conditions, 

 tending early to stabilise their life-forms — the struggle against the 

 polar chills has been favourable to the further variation and 

 adaptation of life ? 



And is not a further pointer in this direction given by the wide 

 development of migration among so many species of birds — all of 

 which agree in their nesting at the pole-ward limit of their annual 

 range, and never nest, so far as yet known, in the warmer climates 

 of their often much longer sojourn? No doubt the abundance of 

 insect and other food in their northern lands at the spring nesting 

 season must be kept in mind; yet is not this, too, an argument for 

 their life-bracing and even life- developing values? And for early 

 upbringing of young especially; indeed, such as we northerners, 

 when in tropic lands, not only look forward to our return, but posi- 

 tively need to send home our children? So, returning to the migratory 

 birds, may we not at least reasonably suspect their origin in these 

 northern lands, though each in later life be tempted or driven to 

 southward climates for more abundant sustenance in its season? 

 And as for our own species, has it not been in the temperate and 

 cold temperate lands that it has mainly developed its powers and 

 civilisations? May we not even have here the element of truth — 

 though in these times so exaggerated — of the vigour and initiative 

 of northern peoples, and so even to reflect that there may be more 

 value than we have generally seen in Mr. Tilak's thesis of "the 

 Arctic Origin of the Aryans", even if we do not locate them quite 

 so far north? 



Notable, too, is the abundance and variety of plankton in the 

 waters of the cold (and even frozen) Arctic and Antarctic seas, in 

 both ways surpassing warmer ones, with its unicellular algae, 

 radiolarians, etc., with eggs and larvse of all kinds as well, thus 

 furnishing ample food for its smaller crustaceans, riiolluscs, etc., 

 which not only in turn feed the fishes, but even the great whales 

 with their vast open mouths for surface-dredge and their whalebone 



