Between 400,000 and 125,000 years ago, caves and open-air sites began to be used. 

Evidence for this comes from sites in Europe. In the Lazaret cave in southern France, a 12x4 metre shelter was built against the cave wall. Inside it were two hearths and evidence of different food sources.

At another site, Terra Amata on the coast of southern France, flimsy shelters with roofs of wood and grasses were built for short-term, seasonal visits.

Hominids have evolved from hominoids and share certain common features, but there are major differences as well: 

The development of writing:
(i) The first Mesopotamian tablets, written around 3200 BCE, contained picture-like signs and numbers. These were about 5,000 lists of oxen, fish, bread loaves, etc. - lists of goods that were brought into or distributed from the temples of Uruk, a city in the south.
Clearly, writing began when society needed to keep records of transactions -because in city life transactions occurred at different times, and involved many people and a involved many people and a variety of goods.
(ii) Mesopotamians wrote on tablets of clay. A scribe would wet clay and pat it into a size he could hold comfortably in one hand. He would carefully smoothen its surfaces.
With the sharp end of a reed cut obliquely, he would press wedge-shaped (‘cuneiform) signs on to the smoothened surface while it was still moist. Once dried in the sun, the clay would harden and tablets would be almost as indestructible as pottery. When a written record of, say, the delivery of pieces of metal had ceased to be relevant, the tablet was thrown away.
(iii) Once the surface dried, signs could not be pressed onto a tablet : so each transaction, however minor, required a separate written tablet.
This is why tablets occur by the hundreds at Mesopotamian sites. And it is because of this wealth of sources that we know so much more about Mesopotamia than we do about contemporary India.
(iv) By 2600 BCE or so, the letters became cuneiform, and the language was Sumerian. Writing was now used not only for keeping records, but also for making dictionaries, giving legal validity to land transfers, narrating the deeds of kings, and announcing the changes a king had made in the customary laws of the land.
Sumerian, the earliest known language of Mesopotamia, was gradually replaced after 2400 BCE by the Akkadian language. Cuneiform writing in the Akkadian language continued in use until the first century CE, that is, for more than 2,000 years.

Prior to the adoption of agriculture, people had gathered plant produce as a source of food. About 160,000 years ago, people obtained food by either scavenging or hunting animals and gathering plant produce. They also learnt how to make stone tools and to communicate with each other. Although other ways of obtaining food were adopted later, hunting-gathering continued.