Enhanced Role of OR Gene Loss (Pseudogenization) in Birds
1.因为文献已经证明（a）基因缺失和得到对于进化有影响，（b）大的基因家族对进化影响更大（because of the broader range of evolutionary pressures that act upon them），所以要研究ORs gene family（big size）对进化的影响：
构建系统生发树：由table4得到鸟类系统生发树：
所以：the olfactory capacity of an organism can be determined by the number of functional and/or nonfunctional ORs（并验证其他paper）
2.描述identify gene numbers：
。。。
统计了48只鸟的ORs gene numbers/partial/pseudo/functional ORs（eg.ORs gene numbers：18456-964-989=16503)
Conversely, if partial genes were considered to be functional, the total number of functional OR genes would still be a low 8,648, highlighting the importance of gene loss in the evolution of the avian OR gene repertoire(少于单个爬行动物的function gene)
3.The alligator and sea turtle
These results suggest that gene loss in sea turtle was higher than in alligator（data）, and that the sea turtle is less reliant on olfaction（biology）
（验证其他paper的结论）These results also suggest that OR gene evolution is shaped by olfaction requirements stemming from different evolutionary ecological, behavioral, and physiological adaptations
（推广）In aggregate, the complete characterization of OR genes into functional and nonfunctional genes suggests that patterns of gene gain and gene loss had an important role in shaping the OR gene repertoires（爬行类）, and thus, the olfactory abilities of different species （所有物种）and patterns among lineages（所有谱系）