1. Given $a+b+c=2, a^{2}+b^{2}+c^{2}=2$. Try to compare the size of the following three expressions:
$$
\begin{array}{l}
a(1-a)^{2}-b(1-b)^{2}-c(1-c)^{2} \\
\text { (fill in “>”, “= ” or “<”). }
\end{array}
$$
ニ、1. $=,=$.
From the given, we have $\left\{\begin{array}{l}a+b=2-c, \\ a^{2}+b^{2}=2-c^{2}\end{array}\right.$.
(1) ${ }^{2}$ - (2) yields $2 a b=2\left(1-2 c+c^{2}\right)$.

Transforming the above equation, we get $a b=(1-c)^{2}$.
Multiplying both sides by $c$ gives $a b c=c(1-c)^{2}$.
Similarly, $a b c=b(1-b)^{2}, a b c=a(1-a)^{2}$.