Ratio of Birds to Mammals
The ratio of birds to mammals is not a fixed number, as the populations of both groups vary greatly depending on the region and environment. Generally speaking, there are more species of birds than mammals, with an estimated 10,000 species of birds compared to around 5,000 species of mammals. However, when it comes to individual numbers, there are far more mammals than birds. Estimates suggest that there are around 200 billion individual birds in the world compared to around 4 billion mammals.
Factors Affecting Bird and Mammal Populations
The ratio of birds to mammals can be affected by a variety of factors including climate change, habitat destruction, hunting and poaching. For example, in areas where deforestation is rampant, bird populations may suffer due to loss of habitat while mammal populations may remain relatively stable. Similarly, hunting and poaching can have a greater impact on mammal populations than bird populations.