Connecting links are organism which shows characters of

$A$ : Blood group analysis shows the human beings are more closely related to apes than to monkeys.
$R$ : The blood groups $A$ and $B$ are found in apes but not in monkeys.

Changes in the body form of some planktonic animals with seasonal changes in temperature are grouped under

The scientist related with the over throw or the "Theory of spontaneous generation'' and experiments with swan-necked flasks is

Which primitive man used stones to produce fire