This is the 11609th most frequent Russian word.
естественных
"естественных" means "natural" in English.
The word 'естественных' is used here to describe 'processes' as natural, referring to phenomena occurring according to the laws of nature.
Есть множество естественных процессов в природе.
There are many natural processes in nature.
In this sentence, 'естественных' modifies 'условиях,' implying that the conditions should be natural, spontaneous, or free from artificial interference.
Обучение должно проходить в естественных условиях.
Learning should take place in natural conditions.
Here, 'естественных' characterizes 'наук,' emphasizing that these sciences deal with natural matters rather than social or abstract concepts.