The gamal refers to both two-humped camels and dromedaries. If you are referring to the same archaeology studies I have looked at, some things need to be born in mind when applying it to the Biblical record and Abraham.
Archaeologists claim domesticated dromedaries were unknown in the land based on dromedary bones not being found prior to the end of the 10th century. That seems to be a stretch to go from the evidence (not used in copper mines) to not used at all prior.
However, Abraham first came from far away in Mesopotamia before settling in Canaan. Artifacts from the region depict two-humped camels in harnesses and being ridden (thus domesticated) dating to the early second millenia. A rich man like Abraham would have camels and take them with him when he moved. Some archaeologists of that region believe the camels were domesticated sometime in the third millenium BC.
Here is a partial list of evidence showing camels in domesticated situations prior to the time of Abraham.
- The ruins of Tall Halaf in Iraq, dating back to the 29th century B.C., depicts a picture of a camel being ridden by a human.
- Evidence from Yemen of camel domestication dates back to the 27th century B.C.
- A house at Mari dating to the 2400s BC contained camel bones.
- A Sumerian text from Nippur (19th century B.C.) refers to camels’ milk.
- A text from the city of Alalakh (18th century B.C.) lists camel food as part of the ration list.
- A relief from Byblos (18th century B.C.) shows a camel kneeling, indicating its use as a beast of burden.
- A terra cotta tablet with men riding on and leading a camel comes from Egypt's pre-dynastic period.
[academic citations for these finds can be found at Western Seminary.]
Interestingly, camels are mentioned in the account of Abraham, but then they disappear from the record until Abraham's grandson Jacob is returning from the place of his ancestors. My conclusion is that the two-humpers were rare in Israel, Abraham brought some with him but they were not replaced. Jacob brought new ones back with him.
More details can be found in Christianity Today, February 2014.