In 2012, Stephan Lautenschlager and colleagues analyzed the complete endocranial anatomy of Erlikosaurus and other therizinosaurs that preserve braincases.
They found that therizinosaurids had well-developed senses of smell, hearing, and balance.
The former two senses may have played an important role during foraging, predator evasion, and complex social behavior.
These senses were also well-developed in earlier coelurosaurs and other theropods, indicating that therizinosaurs may have inherited many of these traits from their carnivorous ancestors and used them for their different and specialized dietary purposes.
Lautenschlager in 2014 tested the function of various therizinosaur hand claws.
He noted that while the claws of other therizinosaurs remained standardised and not highly specialized, Therizinosaurus used their claws when foraging vegetation and probably as threat display or gripping mates during mating as the claws are more elongated, straight and built to withstand higher levels of stress than other members.
These would not have been used for digging, which would have been done with the foot claws because, since as in other maniraptorans, feathers on the forelimbs would have interfered with this function.
However, he could neither confirm nor disregard that the hand claws could have been used for sexual display as in some species of turtles due to the lack of more complete specimens.

The discovery of fossilized embryos at the Nanchao Formation and multiple egg nests from other formations indicates that therizinosaurs had a colonial nesting-style similar to other herbivores like some sauropodomorphs, titanosaurs and hadrosaurs.
Apparently, nestling therizinosaurs were capable of movements after birth and did not necessarily depend of their parents.
It is also indicated that therizinosaurs did not have a philopatric behaviour when nesting.
In 2012, Stephan Lautenschlager and colleagues analyzed the complete endocranial anatomy of Erlikosaurus and other therizinosaurs that preserve braincases. They found that therizinosaurids had well-developed senses of smell, hearing, and balance. The former two senses may have played an important role during foraging, predator evasion, and complex social behavior. These senses were also well-developed in earlier coelurosaurs and other theropods, indicating that therizinosaurs may have inherited many of these traits from their carnivorous ancestors and used them for their different and specialized dietary purposes. Lautenschlager in 2014 tested the function of various therizinosaur hand claws. He noted that while the claws of other therizinosaurs remained standardised and not highly specialized, Therizinosaurus used their claws when foraging vegetation and probably as threat display or gripping mates during mating as the claws are more elongated, straight and built to withstand higher levels of stress than other members. These would not have been used for digging, which would have been done with the foot claws because, since as in other maniraptorans, feathers on the forelimbs would have interfered with this function. However, he could neither confirm nor disregard that the hand claws could have been used for sexual display as in some species of turtles due to the lack of more complete specimens.
The discovery of fossilized embryos at the Nanchao Formation and multiple egg nests from other formations indicates that therizinosaurs had a colonial nesting-style similar to other herbivores like some sauropodomorphs, titanosaurs and hadrosaurs. Apparently, nestling therizinosaurs were capable of movements after birth and did not necessarily depend of their parents. It is also indicated that therizinosaurs did not have a philopatric behaviour when nesting.
Therizinosaurus