Answer:
Shope papilloma virus, mastomys natalensis papillomavirus, and psittacus erithacus timneh papillomavirus
 
        
             
        
        
        
Human exploitation of fragile ecosystems can lead to the droughts and arid conditions characteristic of desertification. Effects include land degradation, soil erosion and sterility, and a loss of biodiversity, with huge economic costs for nations where deserts are growing.
        
             
        
        
        
Conduction is when heat is transferred through direct contact.when molecules get heat they move faster and vibrate then bumping in to other particles transferring the heat passing the energy around
        
             
        
        
        
Crossing over occurs at the four-strand stage when two homologous chromosomes, each consisting of a pair of sister chromatids, are paired. Each crossover involves just two of the four strands and generates two recombinant strands.
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