Dog knows meme? Human has selfish meme?

Here is a funny meme center. http://www.memecenter.com/ . You can check it out.
Thank V for talking about MEME stuff in the blog meme-no-me-me.html. I found this meme center, and found lots of funny pictures.
One I like most is about a dog who does not trust anyone. He is so genius that he considers his paw as enemy to steal the food from him. That's funny.  Check it out. genius-dog-knows-meme

This is a another one.  A big gift for a cat. This makes me laugh. The cat is so cute!

The above is about funny stuff. 
I just found this article the-selfish-meme which is concerned with our selfish meme: we always want to share our thoughts. According to the author, when we share our feeling or thoughts on the social media, we activate our brain reward system and feel satisfied. Based on my experiences, I think posting my thoughts online is indeed making me happy in some ways. When I feel so frustrated or surprising, exciting about something, I feel eager to share with others. I guess others' likes, replies, or retweeting of my tweets are rewarding to me. 

When do you feel eager to share with someone else?