I have two tables.First table having two columns id and birds. Second table has two columns id and animals name. How to fetch this record using mysql and display it in a html single table in different rows.



You can do as
select
@r:=@r+1 as id ,
resultdata from
(
select birds as resultdata from birds
union all
select animals as resultdata from animals
)x,(select @r:=0)n;
union all from the two tables and then using a user defined variable @r to increment it for each record to provide an id as you have shown in the desired result. If you are using PHP then connect to DB using the php code, then execute the above query and then finally do a loop and display the data into the table.
SELECT a.id, a.Birds AS ResultData FROM tableA UNION SELECT b.id, b.Animals AS ResultData FROM tableB.