In the early days, new Twitter users were given an avatar that looked like a businessman walking along; later, it got changed to a bird, and since 2010 it's been an egg. Now Twitter is updating the default avatar again to something much more generic.

The social media site decided it was time for an upgrade. Now, for those people who haven't uploaded profile photos, instead of seeing a white oval inside a bright colored square, you'll see a generic silhouette of a dark gray head and shoulders against a light gray background.

"It's time for something new -- something that encourages people to upload their own photos for more personal expression," Twitter wrote in a blog post

Twitter gives three reasons for the change: to bring the default avatar into line with its recent rebranding efforts, to encourage users to actually get around to personalizing their profile, and to get away from the negative connotations that accounts with egg pictures have drawn in recent years. Originally chosen for being "playful, fun, and unique", the era of the egg avatar is over, Twitter says.

Instead of varied colorful eggs, Twitter said the new default profile image has these traits: generic, universal, serious, unbranded, temporary and inclusive.

Twitter has been tinkering with several of its features over the past few days. On Thursday it announced it was adding a little more room to its 140-character limit in reply tweets. On Wednesday Twitter said videos from Periscope could now play directly in Moments, which is the site's up-to-the-minute curated collection of tweets, videos and discussions.