108 ANIMAL LIFE IN DESERTS 



The Kitlitz Plover (Charadrius pecitarius), which 

 breeds in tropical Africa and which extends down 

 the Nile Valley to Lower Egypt, and its relative 

 Charadrius alexandrinus seehohmi cover their eggs 

 with sand when they leave them. The purpose of 

 this is unknown : it may be protection from foes 

 or from the sun's heat. 



iv. Animals and Wind 



We have already seen (pages 27-30) that wind 

 is a constant element of the desert cUmate, at any 

 rate in summer. It is frequently strong, and even 

 violent ; in many places it is constant in direction, 

 and under certain circumstances columnar vortices 

 are formed which sweep small objects from the 

 surface of the desert and carry them to a great 

 height. It is probable therefore that wind is a 

 great distributor of the seeds of desert plants, and 

 of all the smaller forms of animal life. The great 

 majority of the creatures which it carries before it 

 or sweeps up into the sky are doubtless killed by its 

 violence, but of those which survive a smaU number 

 reach a suitable environment far from their original 

 home. 



It seems probable therefore that wind has had 

 a large share in widening the distribution of many 

 of the plants and animals of the Great Palsearctic 

 Desert, and it is important to remember that the 

 desert wind is barely if at all impeded by herbage 

 and grass, as it is in other types of country. It is 

 therefore felt in its full force even by the small 

 forms of life on the surface of the ground. 



