The control of migration, its timing and response are genetically controlled and appear to be a primitive trait that is present even in non-migratory species of birds. The ability to navigate and orient themselves during migration is a much more complex phenomenon that may include both endogenous programs as well as learning.
What is a primitive trait present even in non migrating birds?
migration

Short-term memory is believed to rely mostly on an acoustic code for storing information, and to a lesser extent a visual code. Conrad (1964) found that test subjects had more difficulty recalling collections of letters that were acoustically similar (e.g. E, P, D). Confusion with recalling acoustically similar letters rather than visually similar letters implies that the letters were encoded acoustically. Conrad's (1964) study, however, deals with the encoding of written text; thus, while memory of written language may rely on acoustic components, generalisations to all forms of memory cannot be made.
What was Conrads deal with?
encoding of written text;

Additionally, the Italian Eritrea administration opened a number of new factories, which produced buttons, cooking oil, pasta, construction materials, packing meat, tobacco, hide and other household commodities. In 1939, there were around 2,198 factories and most of the employees were Eritrean citizens. The establishment of industries also made an increase in the number of both Italians and Eritreans residing in the cities. The number of Italians residing in the territory increased from 4,600 to 75,000 in five years; and with the involvement of Eritreans in the industries, trade and fruit plantation was expanded across the nation, while some of the plantations were owned by Eritreans.
Besides Eritreans, which other nationality increased its city population because of new industries?
Italians