Source Data Figure 1. Amino acid sequences of ancestral anCas.
>FCA_anCas
MKKDYSIGLDIGTNSVGWAVTDDNYNLVRKKMKVLGNTDKKSIGKALWGVRLFDAAETAE
ERRMHRTTRRRYTRRRQRIDLLQEIFQEEISKVDPSFFIRLNESRLHPEDKTDDRHPLFG
DNETDKDYHKQYPTIYHLRKHLMESDEKHDIRLVYLALHHIIKYRGHFLIEGDLNSENTD
VEELFKQLVQVFNDTFEEEHLSEEAIDIEEILTDKKSRSTRAKEVVKLFGSEKKQACISA
LIKLIVGLKGNLKKVFGDAEDTSIHFSKDNYEEDLEAIRDIIPDEYADLFEAIKALYDAI
VLSGILGGSTSNTKAKVSASMIARYEQHQKDLKQLKQFVKEHLPEKYNEIFSDNTKNGYS
AYIEGGTSQEDFYKYLKKILKELEEAEYLLEEIENENFLPKQRTSDNGVIPYQIHLEELR
AILKNQGKYYPFLKENAEKIESILTFRIPYYVGPLARGNGRFAWMIRKKDGKITPWNFDE
VVDKEKSAEEFIERMTNNCTYLPGENVLPKNSLLYEKFTVLNELNNVRLTTDKGKTRRFS
AEQKQEIFDDLFRKNRKVTKKKLEDYLKREYEEFDSADISGIDGEFKSSLGSYHDFCKIV
VKGNSLDEEDYKDIIEEIIKWLTVFEDRKMLRRRLEKYSEILTEEQIKKICKRHYTGWGR
LSRKLLTGIRDKETGKSIIDVLRETDSSNRNFMQLLSDEDLSFKEEIEQANAEAEGENLH
EIVEDLPGSPAIKRGILQALKIVDEIVKVMGHEPKNIFVEMARENQKTGRGRRSTKKRLK
RLQEALKNLGSNLLKELPRDDNELRNDRLFLYYTQMGKCMYTGEPIDLDDLSNYDIDHII
PQSFIKDDSLDNRVLVSREENARKTDNFPSPEIRRKMKSFWQMLLKAGLISKKKFDRLTR
ADRGDFTDDELAGFIARQLVETRQITKHVATLLKQRYPTEKDEEDKTIRNAKIVSVKANL
VSEFRQDFGLYKCREVNDYHHAHDAYLNAVVGNALLKKYPQLAAEFIKGDYRKNNAREEN
KANAKMHFYSNIMNSFTSDVKIADETGEIVWDKEKDIATVRKVMNYHQVLITRKVEEEKG
GFFDQTILSKGNSKKLIPLKKNLDPEKYGGYNSPTVAYSVLVEYDIEKGKKKKLKTVKQL
VGIPIRERAKLEKNPIKYLEKKGYQNPKVDLLIKIPKNSLFELDGGRRRILAAAKELKNA
NQLVLPAEEYTLLDKVAKIIKKNNSESIEYVEEHLSEFDELLESLIDYSPKLALQDKNLE
KIKEAFEQLNLADKKEVAKEIINLLHCTATTANAALKFLGGSKNRMRYTSIKELLNASLI
HQSITGLYETRIDLGKLGED

>BCA_anCas
MKKDYSIGLDIGTNSVGWAVITDDYKVVRKKMKVLGNTDKKSIKKNLWGVRLFDSGETAE
DTRLKRTTRRRYTRRRNRICYLQEIFQEEMNKVDDSFFHRLDESFLVPEDKKYDRHPIFG
NLEEEVAYHEQYPTIYHLRKHLADSSEKADLRLVYLALAHIIKYRGHFLIEGDLNTENTD
VEELFKQFVQVYNQTFEEQHLSDETIDVEEILTEKVSKSRRAENVLKLFPNEKKNGLFGQ
LIKLIVGLQGNFKKVFDLSEDAKLQFSKDTYEEDLENLLAMIGDEYADLFLAAKNLYDAI
LLSGILTTTDNNTKAKLSASMIKRYEEHQKDLAQLKQFIKEHLPDKYNEIFSDSSKNGYA
GYIEGKTSQEDFYKYLKKILSKIDGAEYFLEKIEQENFLRKQRTFDNGVIPHQIHLEELR
AILRRQGKYYPFLKENQEKIEQILTFRIPYYVGPLARGNSRFAWLTRKSDEPITPWNFDE
VVDKEKSAEAFIERMTNYDTYLPNEKVLPKHSLLYEKFTVFNELTKVRYVTDRGKTQNFS
AEQKQEIFDDLFKKNRKVTKKKLENYLKKEYEYFDSPDITGIEDEFNASLGTYHDLLKIL
KSKDFLDDEENEEILEDIVKILTVFEDRKMIRKRLEKYSDILTEEQLKKLERRHYTGWGR
LSRKLINGIRDKQSGKTILDYLIDDDSSNRNFMQLINDDNLSFKEEIEKAQVIGETENLH
EIVQDLPGSPAIKKGILQSLKIVDELVKVMGHEPKNIVVEMARENQTTSRGRRNSKQRLK
RLEEALKNLGSNLLKEHPVDNQQLQNDRLYLYYLQNGKDMYTGQELDIDNLSNYDIDHII
PQSFIKDNSIDNRVLVSSEENRGKSDNVPSKEVVRKMKSFWQKLLNAGLISQRKFDNLTK
AERGGLTEDDKAGFIKRQLVETRQITKHVANILDSRFNTEKDEEDNTIRNVKIITLKSNL
VSQFRKDFGLYKVREINDYHHAHDAYLNAVVGTALLKKYPQLEPEFVYGDYRKNNAREEN
KATAKKHFYSNIMNFFASEVKIADETGEIVWDKEKDIATVRKVLSYHQVNIVKKVEVQKG
GFSKETILPKGNSNKLIPRKNNWDPKKYGGFDSPTVAYSVLVTYDIEKGKKKKLKTVKEL
VGITIMERSAFEKNPIAYLEKKGYQNPQEDVLIKLPKYSLFELENGRRRMLASAKELQKG
NQMVLPAHLVTLLYHAKRIDKSNNSESLEYVEEHRNEFDELLDYIIDFSEKYILADKNLE
KIKKLYEQNNEADIKELAKSFINLLTFTAMGAPAAFKFFGETIDRKRYTSIKELLNATLI
HQSITGLYETRIDLGKLGED

>SCA_anCas
MKKPYSIGLDIGTNSVGWAVITDDYKVPAKKMKVLGNTDKQSIKKNLLGALLFDSGETAE
ATRLKRTARRRYTRRRNRICYLQEIFSEEMNKVDDSFFHRLDESFLVPEDKKYDRHPIFG
NLAEEVAYHEQYPTIYHLRKHLADSTEKADLRLVYLALAHIIKFRGHFLIEGDLNAENTD
VQKLFQQFVEVYNQTFEESHLSEETIDVEEILTEKISKSRRLENLIKHFPNEKKNGLFGN
LIALILGLQPNFKTNFDLSEDAKLQFSKDTYEEDLENLLAQIGDEYADLFLAAKNLYDAI
LLSGILTVTDNSTKAPLSASMIKRYEEHQKDLAQLKQFIKEHLPDKYNEIFSDKSKNGYA
GYIEGKTSQEDFYKYLKKILSKIDGAEYFLDKIDREDFLRKQRTFDNGSIPHQIHLQELH
AILRRQGEYYPFLKENQEKIEKILTFRIPYYVGPLARGNSRFAWLTRKSDEKITPWNFDE
VVDKESSAEAFIERMTNYDTYLPNEKVLPKHSLLYETFTVYNELTKVKYVTERGKTQQFF
SAEQKQEIFDHLFKKNRKVTKKKLKDYLEKEFEEFDSVDITGVEDEFNASLGTYHDLLKI
LKDKDFLDDEENEEILEDIVLTLTLFEDREMIRKRLEKYSDLFTKEQLKKLERRHYTGWG
RLSRKLINGIRDKQSGKTILDYLIDDGSSNRNFMQLINDDSLSFKEEIEKAQVIGETDNL
HEVVQDLAGSPAIKKGILQSLKIVDELVKVMGRHNPENIVVEMARENQTTNRGRRNSRQR
LKRLEEALKNLGSNILKEHPVDNQQLQNDRLYLYYLQNGKDMYTGEELDIDNLSQYDIDH
IIPQSFIKDNSIDNRVLTSSEENRGKSDNVPSIEVVRKMKSFWQKLLNAGLISQRKFDNL
TKAERGGLTEDDKAGFIKRQLVETRQITKHVAQILDSRFNTERDENDKRIRNVKIITLKS
NLVSQFRKDFGLYKVREINDYHHAHDAYLNAVVGTALLKKYPKLEPEFVYGDYKKYNLRK
LIAKSDRERGKATAKMFFYSNIMNFFKTEVKLADGTVIERPVIETNKETGEIVWDKEKDF
ATVRKVLSYPQVNIVKKVEVQTGGFSKESILPKGNSDKLIPRKNNWDPKKYGGFDSPTVA
YSVLVVADVEKGKAKKLKTVKELVGITIMERSAFEKNPIAFLEKKGYQNIQEDLIIKLPK
YSLFELENGRRRLLASAKELQKGNEMVLPAHLVTLLYHAKRIDKSNGNSENLEQKQEYVE
KHKNEFDELLDYIIDFSEKYILADKNLEKIKELYDQNDDADINELASSFINLLTFTALGA
PAAFKFFGETIDRKRYTSTKEVLNATLIHQSITGLYETRIDLSKLGED

>PCA_anCas
MKKPYSIGLDIGTNSVGWAVITDDYKVPAKKMKVLGNTDRQSIKKNLIGALLFDSGETAE
ATRLKRTARRRYTRRKNRICYLQEIFSEEMAKVDDSFFHRLEESFLVPEDKKYDRHPIFG
NLADEVAYHENYPTIYHLRKKLADSTEKADLRLIYLALAHIIKFRGHFLIEGDLNAENTD
VQKLFHQLVDTYNQLFEEDQLDTETIDAKAILTAKISKSRRLENLISQIPGQKKNGLFGN
LIALSLGLTPNFKSNFDLSEDAKLQLSKDTYEEDLDNLLAQIGDQYADLFLAAKNLSDAI
LLSDILTVNDESTKAPLSASMIKRYEEHQQDLALLKQLVKEQLPEKYKEIFSDKSKNGYA
GYIDGKTSQEEFYKYIKPILSKLDGAEEFLAKIDREDFLRKQRTFDNGSIPHQIHLEELH
AILRRQEEYYPFLKDNQEKIEKILTFRIPYYVGPLARGNSRFAWLTRKSDEAITPWNFEE
VVDKEASAQAFIERMTNFDTYLPNEKVLPKHSLLYETFTVYNELTKVKYVTEGMTKPQFL
SAEQKQAIVDLLFKKNRKVTVKQLKEDYFKKIECFDSVDITGVEDRFNASLGTYHDLLKI
IKDKDFLDNEENEDILEDIVLTLTLFEDREMIEKRLAKYADLFDKKVLKKLKRRHYTGWG
RLSRKLINGIRDKQSGKTILDFLKADGFANRNFMQLINDDSLSFKEEIEKAQVIGQTDSL
HEVVADLAGSPAIKKGILQTIKIVDELVKVMGRHNPENIVIEMARENQTTAQGIKNSRQR
MKRLEEVLKKLGSNILKEHPVDNTQLQNDRLYLYYLQNGKDMYTGQELDIDNLSQYDIDH
IIPQSFIKDNSIDNKVLTSSEENRGKSDNVPSIEVVRKMKSYWQKLLNAGLISQRKFDNL
TKAERGGLTESDKAGFIKRQLVETRQITKHVAQILDSRFNTERDENDKPIRNVKIITLKS
KLVSDFRKDFGLYKVREINDYHHAHDAYLNAVVGTALLKKYPKLEPEFVYGDYKKYDLRK
LIAKSDKERGKATAKMFFYSNIMNFFKTEVKLANGTIIKRPVIETNEETGEIVWDKEKDF
ATVRKVLSYPQVNIVKKTEVQTGGFSKESILPKGNSDKLIPRKNNWDPKKYGGFDSPTVA
YSVLVVAKVEKGKAKKLKTVKELVGITIMERSAFEKNPIAFLEAKGYQDIQEDLIIKLPK
YSLFELENGRRRLLASAKELQKGNEMVLPAHLVTFLYHASRIDKSTGSSENLEQKQEYVE
QHKHEFDEILDYIIDFSERYILADKNLEKIKSLYNQNDDSDINELASSFINLFTFTALGA
PAAFKFFDATIDRKRYTSTKEVLNATLIHQSITGLYETRIDLSQLGGD

>PDCA_anCas
MDKKYSIGLDIGTNSVGWAVITDDYKVPSKKFKVLGNTDRHSIKKNLIGALLFDSGETAE
ATRLKRTARRRYTRRKNRICYLQEIFSNEMAKVDDSFFHRLEESFLVEEDKKHERHPIFG
NIVDEVAYHEKYPTIYHLRKKLADSTDKADLRLIYLALAHMIKFRGHFLIEGDLNPDNSD
VDKLFIQLVQTYNQLFEENPINASGVDAKAILSARLSKSRRLENLIAQLPGEKKNGLFGN
LIALSLGLTPNFKSNFDLAEDAKLQLSKDTYDDDLDNLLAQIGDQYADLFLAAKNLSDAI
LLSDILRVNSEITKAPLSASMIKRYDEHHQDLTLLKALVRQQLPEKYKEIFFDQSKNGYA
GYIDGGASQEEFYKFIKPILEKMDGTEELLAKLNREDLLRKQRTFDNGSIPHQIHLGELH
AILRRQEDFYPFLKDNREKIEKILTFRIPYYVGPLARGNSRFAWMTRKSEETITPWNFEE
VVDKGASAQSFIERMTNFDKNLPNEKVLPKHSLLYEYFTVYNELTKVKYVTEGMRKPAFL
SGEQKKAIVDLLFKTNRKVTVKQLKEDYFKKIECFDSVEISGVEDRFNASLGTYHDLLKI
IKDKDFLDNEENEDILEDIVLTLTLFEDREMIEERLKTYAHLFDDKVMKQLKRRHYTGWG
RLSRKLINGIRDKQSGKTILDFLKSDGFANRNFMQLIHDDSLTFKEDIQKAQVSGQGDSL
HEQIANLAGSPAIKKGILQTVKVVDELVKVMGRHKPENIVIEMARENQTTQKGQKNSRER
MKRIEEGIKELGSQILKEHPVENTQLQNEKLYLYYLQNGRDMYVDQELDINRLSDYDVDH
IVPQSFIKDDSIDNKVLTRSDKNRGKSDNVPSEEVVKKMKNYWRQLLNAKLITQRKFDNL
TKAERGGLSELDKAGFIKRQLVETRQITKHVAQILDSRMNTKYDENDKLIREVKVITLKS
KLVSDFRKDFQFYKVREINNYHHAHDAYLNAVVGTALIKKYPKLESEFVYGDYKVYDVRK
MIAKSEQEIGKATAKRFFYSNIMNFFKTEITLANGEIRKRPLIETNGETGEIVWDKGRDF
ATVRKVLSMPQVNIVKKTEVQTGGFSKESILPKRNSDKLIARKKDWDPKKYGGFDSPTVA
YSVLVVAKVEKGKAKKLKSVKELVGITIMERSSFEKNPIDFLEAKGYKDVQKDLIIKLPK
YSLFELENGRRRMLASAGELQKGNEMVLPAKLVTFLYHASHIEKSKGSPENNEQKQAYIE
QHKHDLDEILEYISEFSKRYILADKNLSKVKSLFNKHEDSSISELASSIINLFTLTSLGA
PAAFKFLDTTIDRKRYTSTKEVLDATLIHQSITGLYETRIDLSQLGGD