The tree was constructed based on alignment done with MUSCLE and Maximum Likelihood (ML) algorithm using MEGA 6 software. Statistical confidence of the evolutionary analysis was assembled by bootstraps of 1000 replicates. Sequences were obtained from GenBank Database. Gorilla FB (Q864V9), Chimpanzee FB (Q864W0), Human FB (P00751), Orangutan FB (Q864W1), Marmoset FB (JAB17376.1), Mouse FB-1 (P04186), Mouse FB-2 (B8JJM5), Ox-FB (P81187), Boar FB (ABX82825.1), Snake FB (AAR21601.1), Frog FB (BAA06179.1), Frog FB-2 (AAI70192.1), Trout C2/FB (ADY68777.1), Trout FB 1 (AAC83699.1), Pufferfish FB/C2 OS (CAD21938.1), Catfish FB/C2 A (AEW10545.1), zebrafish FB (AAB19093.1), Carp FB/C2 A3 (BAB32650.1), Carp FB/C2 A2 (BAA78416..1), Carp FB/C2 A (BAA34706.1), Houndshark FB (BAB63203.1), Houndshark FB 2 (BAF62177.1), Catfish FB (AEW38662.1), Carp FB/C2 B (BAA34707.1), Trout C2/FB 2 (BAB19788.1), Mouse C2 (P21180), Ox C2 (Q3SYW2), Orangutan C2 (Q8SQ74), Gorilla C2 (Q863A0), Human C2 (P06681), Chimpanzee C2 (Q8SQ74), Lamprey FB (BAA02763.1), Lamprey FB 2 (BAG66069.1), Ascidia FB (AAK00631.1), Ciona FB-3 (BAD89301.1), Ciona FB-1 (BAD89299.1), Ciona FB-2 (BAD89300.1), Amphioxus FB/C2 (ABY28382.1), Anemone FB (BAH22726.1), Anemone FB 2 (BAH22728.1), Bivalve FB (ACQ91095.1), Sea cucumber FB 2 (AEP68015.1), Sea cucumber FB (ADX36428.1), Sea urchin FB (AAC79682.1), Horseshoe crab 1 C2/FB 1 (BAM15262.1), Horseshoe crab 1 C2/FB 2 (BAM15263.1), Horseshoe crab 2 C2/FB 1 (AAV65032), Horseshoe crab 2 C2/FB 2 (ABK30937.1), Jumping spider FB1 (BAR45590-1),Jumping spider FB2 (BAR45591.1), Jumping spider FB3 (BAR45592.1), sea spider FB 1 (BAR45606.1), sea spider FB 2 (BAR45607.1), centipede FB 1 (BAR45616.1), centipede FB 2 (BAR45617.1).