XViii CONTENTS 



319. The Tarsioids 739 



320. The Anthropoids 740 



321. The Modern Great Apes 741 



322. The Man Apes 743 



323. Fossil Ape Men 744 



324. Modern Man (Homo sapiens) 749 



325. Cultural Evolution 751 



Part V. Animals and Their Environment 



Chapter 37 



ECOLOGY 753 



326. Ecosystems 753 



327. Habitat and Ecologic Niche 755 



328. The Cyclic Use of Matter 755 



329. The Carbon Cycle 756 



330. The Nitrogen Cycle 757 



331. The Water Cycle 758 



332. Mineral Cycles 758 



333. The Energy Cycle 759 



334. Physical Factors in the Environment 759 



335. Types of Interactions between Species 763 



336. Competition 763 



337. Commensalism 764 



338. Protocooperation 764 



339. Mutualism 765 



340. Amensalism 765 



341. Parasitism and Predation 765 



342. Intraspecific Relations 766 



343. Food Chains 767 



344. Communities and Populations 768 



345. Populations and Their Characteristics 769 



346. Population Cycles 773 



347. Population Dispersal 775 



348. Biotic Communities 775 



349. Community Succession 777 



350. The Dynamic Balance of Nature 779 



Chapter 38 



THE ADAPTATION OF ANIMALS TO THE ENVIRONMENT 781 



351. Adaptive Radiation 782 



352. Convergent Evolution 783 



