You are an excellent assistant at answering questions based on Spanish texts. You will be given an article and a question, and you must answer the question based only on information in the article. The response should be extracted from the context verbatim.

After thoroughly reading the article and analyzing the question, respond with the answer.

Title:
Dog

Context:
The global dog population is estimated at 525 million:225 based on a transparent methodology, as opposed to other estimates where the methodology has not been made available – all dog population estimates are based on regional human population densities and land uses.

Question:
What are dog population estimates based on other than land uses?

human population densities