Challenge 2: Tom says that Judith says that Margaret says that Elly is an elephant. What species are Tom, Judith, Margaret, and Elly?

Following is my answer to the above question.

Possibilities  :

There are 4 possibilities for the statements of Tom and Judith. TT, TL, LT, LL ( LT means that Tom is lying and Judith is telling the truth, etc).

Also, note one thing.

If Margaret said that Elly is an elephant then Elly can be either a dinosaur or an elephant. In both these cases, Margaret will be an elephant. Margaret cannot be a dinosaur.

If Margaret said that Elly is a dinosaur then Margaret is a dinosaur and Elly can be a dinosaur or an elephant. Margaret cannot be an elephant, in this case.

Now, if Judith is telling the truth then this would mean that Margaret indeed said that Elly is an elephant. In this case, both Judith and Margaret are elephants.

If Judith is lying then Margaret said that Elly is a dinosaur. In this case, Margaret is a dinosaur and Judith is an elephant.

So,

TT = Judith, Margaret are elephants, Elly can be anything and Tom is also an elephant.

TL = Judith is an elephant, Margaret is a dinosaur, Elly can be anything and Tom is an elephant.

LT = Judith  , Margaret are elephants, Elly can be anything and Tom is a dinosaur

LL = Judith is an elephant, Margaret is a dinosaur and Tom is a dinosaur. Elly can be anything  .

Here is a table to summarise this.

In conclusion, Judith will be an elephant no matter what. For all the others, please refer to the table above.

Challenge 2: Tom says that Judith says that Margaret says that Elly is an elephant. What species are Tom, Judith, Margaret, and Elly?

Following is my answer to the above question.

Possibilities:

There are 4 possibilities for the statements of Tom and Judith. TT, TL, LT, LL ( LT means that Tom is lying and Judith is telling the truth, etc.).

Also, note one thing.

If Margaret said that Elly is an elephant then Elly can be either a dinosaur or an elephant. In both these cases, Margaret will be an elephant. Margaret cannot be a dinosaur.

If Margaret said that Elly is a dinosaur then Margaret is a dinosaur and Elly can be a dinosaur or an elephant. Margaret cannot be an elephant, in this case.

Now, if Judith is telling the truth then this would mean that Margaret indeed said that Elly is an elephant. In this case, both Judith and Margaret are elephants.

If Judith is lying then Margaret said that Elly is a dinosaur. In this case, Margaret is a dinosaur and Judith is an elephant.

So,

TT = Judith, Margaret are elephants, Elly can be anything and Tom is also an elephant.

TL = Judith is an elephant, Margaret is a dinosaur, Elly can be anything and Tom is an elephant.

LT = Judith, Margaret are elephants, Elly can be anything and Tom is a dinosaur

LL = Judith is an elephant, Margaret is a dinosaur and Tom is a dinosaur. Elly can be anything.

Here is a table to summarise this.

In conclusion, Judith will be an elephant no matter what. For all the others, please refer to the table above.