A strong acid is a number between 0-6 on the pH scale and Bases are between 8-14 on the pH scale the difference is how much hydroxide each one has like coca-cola (acid) and backing soda (base)
I think the common between low-latitude countries would be people's skin color and If you compare the Philippines and its neighboring countries, they have more or less similar physical attributes. Typical Filipinos looked similar with Indonesians.
For Southeast Asia, i would also consider religion is common between the two. Both the Philippines and the other Southeast Asian countries such as Indonesia, Malaysia, and Thailand, they have a large number of Muslim settlers while other tropical countries in South America, these countries have similar Spanish ancestry just like the Philippines.
Polaris directly over head.
Thats the only thing I can think of if you have options I could answer better.
I am pretty sure it it central Africa
