What are the conditions on earth billions years ago

Look at the picture below . what does this picture represent ?

Scenario #2 in 2001, a population of 2,500 poison dart frogs lived in the amazon rain forest. due to increased deforestation, the population dwindled to 25 frogs in 2019. new government regulations were enacted in 2022, successfully putting an end to the deforestation of the amazon rain forest. once deforestation was stopped, the poison dart frog population was able to recover. by 2050, the population reached 8,000 frogs, of that population, 20 are homozygous recessive for being spotted (ss genotype). q2- ? q- p- p2- 2pq-

When lactate builds up in a runners muscles it causes a burning sensation what causes this to occur