Project 268: D. W. Fowler, E. A. Freedman, J. B. Scannella. 2009. Predatory functional morphology in raptors: Interdigital variation in talon size is related to prey restraint and immobilisation technique. PLOS ONE. 4 (11):1-9.
Specimen: Strix nebulosa (:MOR-OST-1284)

Abstract

Despite the ubiquity of raptors in terrestrial ecosystems, many aspects of their predatory behaviour remain poorly understood. Surprisingly little is known about the morphology of raptor talons and how they are employed during feeding behaviour.

Talon size variation among digits can be used to distinguish families of raptors and is related to different techniques of prey restraint and immobilisation. The hypertrophied talons on digits (D) I and II in Accipitridae have evolved primarily to restrain large struggling prey while they are immobilised by dismemberment. Falconidae have only modest talons on each digit and only slightly enlarged D-I and II. For immobilisation, Falconini rely more strongly on strike impact and breaking the necks of their prey, having evolved a ‘tooth’ on the beak to aid in doing so. Pandionidae have enlarged, highly recurved talons on each digit, an adaptation for piscivory, convergently seen to a lesser extent in fishing eagles. Strigiformes bear enlarged talons with comparatively low curvature on each digit, part of a suite of adaptations to increase constriction efficiency by maximising grip strength, indicative of specialisation on small prey. Restraint and immobilisation strategy change as prey increase in size. Small prey are restrained by containment within the foot and immobilised by constriction and beak attacks. Large prey are restrained by pinning under the bodyweight of the raptor, maintaining grip with the talons, and immobilised by dismemberment (Accipitridae), or severing the spinal cord (Falconini).

Within all raptors, physical attributes of the feet trade off against each other to attain great strength, but it is the variable means by which this is achieved that distinguishes them ecologically. Our findings show that interdigital talon morphology varies consistently among raptor families, and that this is directly correlative with variation in their typical prey capture and restraint strategy.



Read the article »

Project DOI: 10.7934/P268, http://dx.doi.org/10.7934/P268
This project contains
  • 282 Media
  • 62 Taxa
  • 152 Specimens
Total size of project's media files: 547.64M

Download Project SDD File
Currently Viewing:
MorphoBank Project 268

    Authors' Institutions

    • Montana State University

    • Museum of the Rockies



    Members

    member name taxa specimens media
    Denver Fowler
    Project Administrator
    62152281
    John Horner
    Full membership
    000


    Project has no matrices defined.



    Project views

    type number of views Individual items viewed (where applicable)
    Total project views159119
    Project overview4431
    Media views75998Media search (4109 views); M26873 (478 views); M26864 (444 views); M26887 (454 views); M26908 (464 views); M26959 (474 views); M26985 (173 views); M26867 (487 views); M26861 (489 views); M26913 (460 views); M26926 (395 views); M26944 (425 views); M26880 (811 views); M26953 (442 views); M26897 (459 views); M26896 (446 views); M26933 (457 views); M26971 (221 views); M26907 (485 views); M26909 (391 views); M26910 (446 views); M26911 (447 views); M26912 (439 views); M26914 (417 views); M26915 (436 views); M26916 (439 views); M26917 (466 views); M26918 (436 views); M26919 (414 views); M26920 (457 views); M26921 (412 views); M26922 (554 views); M26923 (477 views); M26924 (430 views); M26925 (422 views); M26927 (417 views); M26928 (430 views); M26929 (416 views); M26930 (414 views); M26931 (424 views); M26932 (393 views); M26934 (440 views); M26935 (435 views); M26936 (442 views); M26937 (460 views); M26938 (402 views); M26939 (456 views); M26940 (411 views); M26941 (420 views); M26942 (417 views); M26943 (462 views); M26945 (413 views); M26946 (419 views); M26947 (407 views); M26948 (422 views); M26949 (453 views); M26950 (458 views); M26951 (432 views); M26952 (474 views); M26954 (472 views); M26955 (430 views); M26956 (477 views); M26957 (435 views); M26958 (409 views); M26960 (432 views); M26961 (492 views); M26962 (176 views); M26963 (166 views); M26964 (197 views); M26965 (171 views); M26966 (215 views); M26967 (221 views); M26968 (219 views); M26969 (162 views); M26970 (201 views); M26972 (172 views); M26973 (221 views); M26974 (208 views); M26975 (212 views); M26976 (231 views); M26977 (168 views); M26978 (231 views); M26979 (197 views); M26980 (225 views); M26981 (227 views); M26982 (168 views); M26983 (226 views); M26984 (177 views); M26986 (245 views); M26987 (239 views); M26891 (483 views); M26889 (475 views); M26874 (485 views); M26885 (494 views); M26870 (471 views); M26888 (481 views); M26902 (429 views); M27000 (239 views); M27009 (194 views); M26905 (412 views); M26871 (474 views); M26882 (487 views); M26894 (453 views); M27064 (172 views); M26884 (491 views); M27077 (213 views); M26881 (472 views); M27024 (223 views); M27069 (224 views); M26898 (468 views); M27025 (277 views); M27057 (229 views); M27008 (199 views); M26879 (493 views); M27021 (221 views); M26890 (450 views); M26995 (191 views); M27059 (176 views); M26868 (472 views); M26865 (451 views); M26904 (423 views); M26877 (467 views); M26878 (465 views); M26901 (463 views); M26903 (460 views); M27013 (205 views); M26875 (462 views); M27135 (8 views); M27073 (218 views); M27080 (226 views); M26892 (466 views); M27032 (198 views); M26876 (508 views); M26991 (239 views); M26872 (471 views); M27051 (190 views); M27084 (198 views); M27017 (186 views); M26863 (486 views); M26906 (439 views); M26869 (463 views); M26993 (224 views); M26899 (453 views); M26999 (236 views); M27094 (7 views); M26886 (468 views); M26866 (476 views); M26893 (483 views); M26883 (463 views); M26900 (499 views); M27130 (4 views); M26895 (461 views); M27010 (216 views); M27082 (192 views); M27028 (225 views); M27049 (244 views); M27071 (183 views); M27078 (231 views); M27003 (223 views); M27048 (189 views); M27062 (244 views); M27037 (232 views); M27029 (174 views); M27050 (241 views); M27006 (242 views); M27086 (228 views); M27027 (186 views); M27045 (194 views); M27034 (239 views); M27083 (187 views); M26990 (199 views); M27068 (197 views); M26996 (238 views); M27001 (222 views); M27055 (248 views); M27047 (178 views); M26988 (219 views); M27063 (169 views); M27007 (181 views); M27081 (239 views); M27067 (222 views); M27053 (223 views); M27002 (172 views); M27074 (181 views); M26998 (220 views); M26989 (205 views); M27044 (213 views); M27085 (179 views); M27128 (19 views); M27065 (183 views); M27012 (199 views); M27075 (217 views); M26997 (193 views); M27030 (227 views); M27058 (176 views); M27079 (231 views); M27060 (224 views); M27091 (7 views); M27076 (193 views); M27018 (221 views); M26992 (236 views); M27041 (177 views); M27098 (5 views); M27005 (163 views); M27040 (245 views); M27019 (187 views); M27023 (214 views); M27061 (229 views); M26994 (228 views); M27042 (228 views); M27033 (184 views); M27070 (241 views); M27004 (161 views); M27072 (225 views); M27111 (5 views); M27066 (232 views); M38450 (4 views); M27054 (194 views); M27031 (214 views); M27036 (228 views); M27056 (181 views); M27102 (5 views); M27090 (4 views); M27043 (220 views); M27038 (178 views); M27124 (4 views); M27052 (239 views); M27014 (239 views); M27039 (188 views); M27020 (190 views); M27046 (180 views); M27026 (169 views); M27016 (235 views); M27022 (213 views); M27011 (188 views); M27100 (5 views); M27015 (231 views); M27035 (183 views); M27097 (26 views); M27136 (13 views); M27113 (5 views); M27115 (7 views); M27105 (5 views); M27114 (7 views); M27095 (6 views); M27092 (6 views); M27120 (6 views); M27121 (5 views); M27110 (6 views); M27123 (7 views); M27129 (6 views); M27104 (6 views); M27112 (5 views); M27088 (7 views); M27089 (6 views); M27096 (5 views); M27125 (5 views); M27140 (6 views); M27127 (6 views); M27093 (5 views); M27109 (5 views); M27116 (8 views); M86105 (5 views); M27108 (8 views); M27139 (4 views); M27119 (5 views); M27106 (5 views); M27132 (5 views); M27107 (6 views); M27118 (4 views); M27137 (5 views); M27133 (6 views); M27087 (5 views); M27117 (4 views); M27103 (4 views); M27101 (5 views); M27134 (4 views); M27126 (4 views); M27099 (6 views); M27138 (4 views); M27131 (5 views); M27122 (5 views); M27141 (4 views);
    Taxon list11081
    Specimen list67008
    Bibliography598
    Documents list3




    Project downloads

    type number of downloads Individual items downloaded (where applicable)
    Total downloads from project294
    Project downloads292
    Media downloads2M26861 (1 download); M27052 (1 download);