MAMMALS 

Mammals need Melatonin (a hormone that is only produced in the darkness) to sleep. However excessive lighting, especially the blue light that radiates from our electronic devices, is disrupting the biological sleep pattern.

Lack of Melatonin causes an increase in chances of acquiring sleep disorders, Diabetes, depression, heart conditions, and breast cancer.

Studies show that ALAN (artificial lighting at night) has been associated with diabetes, fatigue and depression, and prostate cancer incidence (This has been deeply researched by Rybnik ova et al; on the basis of World Bank Databases).

 Bats use a commuter route system when heading towards feeding areas, but streetlamps tend to create barriers of light, which bats are hesitant to cross. This disturbs their cycle of feeding and ultimately has a vast effect on the insect-population management these species provide.