After a string of hits and international success, The Turtles folded in 1970. Mark, Howard and Jim Pons joined Frank Zappa's Mothers of Invention, for one of the most entertaining incarnations of that ensemble.
Due to contractual restrictions made early in their career, Mark and Howard were prevented from using the name "The Turtles", as well as their own names, in a musical context. In order to circumvent this, they became "The Phlorescent Leech and Eddie" (later shortened to "Flo and Eddie").
While with The Mothers, they appeared on

• Chunga's Revenge
• 200 Motels
• Live At The Fillmore
• Just Another Band From L.A.

...as well as appearing in the film '200 Motels'.
Interesting to note... early in the Mothers' career, Reb Foster, an L.A. disk jockey (and Turtles' manager) had told Zappa, "I'd like to clean you guys up a bit and mold you. I believe I could make you as big as The Turtles."

Disaster struck twice. First, the incident at Montreux, Switzerland, chronicled in Deep Purple's song "Smoke On The Water", where the concert hall in which The Mothers were performing burned down. Then Frank Zappa was attacked by the irate boyfriend of a fan during a concert appearance in England. After Zappa's injury in London, Mark and Howard continued touring, as Flo & Eddie, initially with the musicians from the Mothers' lineup, including Jim Pons, Aynsley Dunbar and Don Preston, with Gary Rowles added on guitar.

Flo & Eddie recorded several excellent albums:

The Phlorescent Leech & Eddie (1972)	Flo & Eddie (1973)	Illegal, Immoral and Fattening (1975)
Moving Targets (1976)	Rock Steady With Flo & Eddie (1981)	The Best of Flo & Eddie (1987)
	The Turtles featuring Flo&Eddie Captured Live!(1992)

 

With the dissolution of the first Flo & Eddie Band, Mark and Howard turned their sites to broadcasting. Howard Kaylan explains:
"I began broadcasting in the Summer of '65 at UCLA before the Turtles' career ever took off.
"Later, in the early eighties, Mark and I did a guest shot on KROQ in L.A. and they liked it so much they gave us our own Sunday Night show which was produced by, then program director, Shadoe Stevens. When Shadoe left for a loftier position on KMET, the big alternative station at the time, we went with him.

"Later in the 80's, we brought the same wacky show to WLIR in New York on a Sunday Night basis...sometimes we were actually there, but most times we recorded the shows in Los Angeles and sent them the tapes."

Having established a relationship with Murakami Wolf Productions while appearing in Frank Zappa's film "200 Motels", they created the voices and music for the animated feature "Dirty Duck". This led to work on music for the animated series "Strawberry Shortcake" and "The Care Bears".
Around the same time, the group evolved "The Two-and-a-Half-Man Show", featuring Mark, Howard and Andy Cahan in a "History of..." presentation, highlighted by their low-budget version of Pink Floyd's 'The Wall' called 'Flo & Eddie's The Fence'.

Howard continues Flo & Eddie's further radio adventures:
"In 1989, we were offered a REAL job...and went for it.
"We were on the air every day between 2pm and 6pm on 92.3 K-ROCK (WXRK) in New York City...the same station that STILL hosts the Howard Stern show. We did almost 2 years on the radio in Manhattan.
So, we go to Cincinnatti or Louisville or Atlanta for a week at a time to promote a show or just for the fun of it... just to keep our hands in the radio biz...I still like it...."