Penguins are the only bird that cannot fly even though they have wings. It must be frustrating but this is how God created them. Penguins preen their feathers to prevent water infiltration. This is a crucial facet of penguin biology since maintaining a high degree of air insulation is vital to their survival for some penguins. Penguins will gather oil from a preening gland located on the rump from where the tail originates. This oil is applied to feathers and to the edges of flippers; oil on the flippers is subsequently transfered to the unreachable regions of the head. Following preening, the penguin will rub the flipper over the region while rotating its body as it coasts along the water. It appears as if the penguin is side-stroking. Another aspect of self-maintenance entails huddling. Penguins, especially young, gather together to minimize heat loss. Penguins release heat through several activities: panting, lifting wings, stream-lining feathers or entering the water. Stream-lining feathers reduces the volume of air between the volume of air between the skin and the edge of the feathers. This layer of air serves as an insulator, and when it is minimized, heat easily is expelled from the body. Penguins eat small fish and crustaceans; however, larger penguins like the emperor or king penguin have been known to take larger fish and even squid. When attcking their prey, generally penguins approach fish from the side, and when caught, they rotate the fish in their bills so that they are swallowed head first. All birds reproduce sexually: males transfer sperm to the female through the cloaca. During copulation, the event of contact between the two cloacas is known as the cloacal kiss. There are four principal parts to the male reproductive tract: the testes, the epididymis, the ductus deferens and a sperm storage location near the cloaca (the commmon orifice). The testes are located dorsally. The testes seem to demonstrate extensive morpholical changes throughout the year, the height of such size change during the breeding season. The increase in testis volume control occured over 8 stagesof data with Adelie penguins. The increase in testis volume occured over 8 stages of spermatogenesis. Stage 1 (n=16 cases observed). A row of spermatogonia and Sertoli cells ring the seminiferous tubucle next to the basement membrane. Primary spermatocytes are present in an irregular row toward the lumen. The lumen is filled with sytoplasm. Stage 2 (n=20). There is a basal row of spermatogia and Sertoli cells. Up to one-half the primary spermatocytes in a given tubule cross section are in the stage of synapsis where chromatin is concentrated to one side of the nucleus. Stage 3 (n=2). A basal row of spermatogia and Sertoli cells ring the basement membrane. Towards the lumen two to three rows of primary spermatocytes are in synapsis. Stage 4 (n=2). A row of secondary spermatocytes lies toward the lumina of tubules. Peripheral to these are cells of previous stages. Stage 5 (n=7). Spermatids are present surrounding the lumina. Intertubular cells are almost completely confined to the triangles formed by the meeting of three tubules. Stage 6 (n=10). Rining the lumina are bundles of spermatozoa with their heads pointing toward the basement membrane. The lumina are filled with cytoplasm. This stage represents breeding condition. Stage 7 (n=10). In this, the climactic stage of spermatogenesis, spermatozoa and cytoplasmic particles are present in the luminia. Stage 8 (n=13). The stage of degeneration where the various cells from all stages in spermatogenesis, except spermatogonia, discharge into the luminia.

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