A "Living Fossil" Because its basic body design has remained almost unchanged for millions of years, the horseshoe crab is often called a "living fossil".
(its basic body design; has remained; almost unchanged; T:for millions of years) (the horseshoe crab; is called; a "living fossil; T:often)
its basic body design the horseshoe crab
has remained is called
almost unchanged T:for millions of years
a "living fossil T:often