"Kamuflaj, hayvanların bazılarının, kendilerini ortama uydurarak düşmanlarından kurunmasıdır."

...and what is it used for?

camouflage means some of the animals protect themselves from their enemies adapting ( being adapted )  to place where they are

To quote from some of my textbooks, the (y)erek/arak suffix  (by ....ing, ....ing), which is added to verbs, indicates action simultaneous with the main verb of the sentence. The two actions can also be in immediate sequence, and can also indicate the way something is done.

Some examples given:

Bankadan para alarak alışverişe gittim.

Taking money from the bank, I went shopping.

Haberi alınca koşarak geldim.

When I got the news I came running.

İstasyona yürüyerek gittim.

I went to the station on foot. (by walking)

Telefon ederek haber vereceğim.

I will give (them) the news by phoning. (I´ll tell them by phone)

Bir şey söylemerek çıktı.

He left without saying anything. (not saying)

Gülerek gitti.

She left smiling. (She went smiling.)

The verb ´olmak´ takes on a special meaning when used with this suffix.

Olarak literally translates as ´being´, but generally means ´as´.

Türkiye´de turist olarak dört ay kaldım.

I stayed in Turkey for four months as a tourist.

Programcı olarak çalışıyorum.

I work as a programmer.

Tatlı olarak ne var?

What is there as dessert?

Arkadaş olarak kalalım.

Let´s stay (as) friends. (Let´s remain friends.)

Hope this helps you. 

Thanks, turkishmaster and Henry. Your examples make it quite clear: what a neat and handy verb form!

I wish I could one day be able to explain something to another learner  -  even if it was a very small thing...

I have also been helped on this site by both Turks and advanced learners, so it is nice to give something back to help others. 

There is so much useful information accumulated on this site, especially when you search through older posts. Most serious learners eventually need good explanations of the different suffixes and their usage. Luckily there are some very helpful people on this site that often explain things better than the language books!