I did my search on genealogy and slavery. I am in the process of undertaking our family history pre-1886. This is the date of my earliest born relative. Google, Yahoo, and Bing were chosen as the individual search engines and Dogpile, WebCrawler, and Ask were the chosen meta-search engines.
The similarities that I find between the two search engines is that they both attempt to direct the researcher according to the key words placed in the string box. In placing my query, all of the search engines referred Ancesty.com in at least the top five results.
A major difference is that the relevance in the individual search topic appeared more readily and more information was given in the individual search engine. There also seems to be more URLs with domain names that appear to be more credible. Some meta-search engines have questionable references or do not immediately address the search unless one of the Boolean Operators is used. I also find quite a bit of ads in some of the meta-search engines which makes me want to question the sites purpose. This is not to say that all meta-search engines are not useful. In my investigation, I found Dogpile.com to have as much CRAAP as Google. Many of my classmates found the opposite. Certainly the search inquiry may have a lot to do with it.