Bifidobacteria represent one of the first colonizers of the mammalian gut, where such colonization is facilitated by their saccharolytic capabilities. Genomic analyses of bifidobacteria have revealed intriguing genetic strategies employed by these bacteria to access a variety of dietary and host-produced glycans. Bifidobacterial genome evolution therefore represents a fascinating example of how their chromosomes were molded to contain a large number of genes involved in carbohydrate metabolism. One of the reasons as to why bifidobacteria are such dominant and prevalent members of the (early) microbiota is that they may access glycans in the gut through mutualistic cross-feeding or resource-sharing activities, which is indicative of ‘social behavior’ among bifidobacterial strains.

双歧杆菌代表哺乳动物肠道的第一批定居者之一，其中通过其糖酵解能力促进了这种定居。双歧杆菌的基因组分析表明，这些细菌采用了有趣的遗传策略来获取各种饮食和宿主产生的聚糖。因此，双歧杆菌基因组进化代表了一个令人着迷的例子，说明它们的染色体是如何模制成含有大量参与碳水化合物代谢的基因的。双歧杆菌为何是（早期）微生物群中如此占主导地位和普遍性成员的原因之一是，它们可能会通过相互交叉喂养或资源共享活动而进入肠道中的聚糖，这表明双歧杆菌中的“社会行为”株。