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
    Last logged in 11/25/09
    62152281
    John Horner
    Full membership
    Last logged in Never
    000


    Project has no matrices defined.



    Project views

    type number of views Individual items viewed (where applicable)
    Total project views151501
    Project overview4296
    Media views71953Media search (3930 views); M26873 (456 views); M26864 (420 views); M26887 (433 views); M26908 (451 views); M26959 (460 views); M26985 (160 views); M26867 (464 views); M26861 (467 views); M26913 (442 views); M26926 (379 views); M26944 (410 views); M26880 (786 views); M26953 (424 views); M26897 (437 views); M26896 (426 views); M26933 (440 views); M26971 (205 views); M26907 (466 views); M26909 (378 views); M26910 (429 views); M26911 (431 views); M26912 (424 views); M26914 (403 views); M26915 (417 views); M26916 (421 views); M26917 (450 views); M26918 (418 views); M26919 (398 views); M26920 (440 views); M26921 (395 views); M26922 (512 views); M26923 (458 views); M26924 (414 views); M26925 (408 views); M26927 (400 views); M26928 (415 views); M26929 (401 views); M26930 (399 views); M26931 (407 views); M26932 (378 views); M26934 (423 views); M26935 (416 views); M26936 (425 views); M26937 (444 views); M26938 (387 views); M26939 (440 views); M26940 (394 views); M26941 (406 views); M26942 (400 views); M26943 (446 views); M26945 (398 views); M26946 (405 views); M26947 (392 views); M26948 (406 views); M26949 (438 views); M26950 (442 views); M26951 (415 views); M26952 (456 views); M26954 (456 views); M26955 (415 views); M26956 (460 views); M26957 (418 views); M26958 (394 views); M26960 (416 views); M26961 (475 views); M26962 (162 views); M26963 (152 views); M26964 (183 views); M26965 (157 views); M26966 (202 views); M26967 (206 views); M26968 (206 views); M26969 (148 views); M26970 (187 views); M26972 (158 views); M26973 (206 views); M26974 (192 views); M26975 (197 views); M26976 (218 views); M26977 (155 views); M26978 (216 views); M26979 (181 views); M26980 (212 views); M26981 (213 views); M26982 (155 views); M26983 (207 views); M26984 (163 views); M26986 (229 views); M26987 (226 views); M26891 (463 views); M26889 (453 views); M26874 (463 views); M26885 (470 views); M26870 (450 views); M26888 (460 views); M26902 (411 views); M27000 (222 views); M27009 (181 views); M26905 (398 views); M26871 (452 views); M26882 (467 views); M26894 (433 views); M27064 (158 views); M26884 (469 views); M27077 (200 views); M26881 (447 views); M27024 (210 views); M27069 (211 views); M26898 (445 views); M27025 (264 views); M27057 (211 views); M27008 (185 views); M26879 (471 views); M27021 (204 views); M26890 (432 views); M26995 (174 views); M27059 (160 views); M26868 (452 views); M26865 (428 views); M26904 (402 views); M26877 (448 views); M26878 (445 views); M26901 (441 views); M26903 (437 views); M27013 (192 views); M26875 (443 views); M27135 (8 views); M27073 (200 views); M27080 (208 views); M26892 (443 views); M27032 (180 views); M26876 (486 views); M26991 (222 views); M26872 (447 views); M27051 (173 views); M27084 (179 views); M27017 (170 views); M26863 (460 views); M26906 (423 views); M26869 (437 views); M26993 (210 views); M26899 (429 views); M26999 (220 views); M27094 (7 views); M26886 (449 views); M26866 (457 views); M26893 (461 views); M26883 (441 views); M26900 (474 views); M27130 (4 views); M26895 (437 views); M27010 (200 views); M27082 (176 views); M27028 (211 views); M27049 (222 views); M27071 (166 views); M27078 (214 views); M27003 (208 views); M27048 (172 views); M27062 (227 views); M27037 (216 views); M27029 (161 views); M27050 (225 views); M27006 (228 views); M27086 (211 views); M27027 (172 views); M27045 (177 views); M27034 (223 views); M27083 (170 views); M26990 (185 views); M27068 (180 views); M26996 (222 views); M27001 (206 views); M27055 (231 views); M27047 (161 views); M26988 (201 views); M27063 (154 views); M27007 (167 views); M27081 (222 views); M27067 (205 views); M27053 (205 views); M27002 (159 views); M27074 (165 views); M26998 (203 views); M26989 (188 views); M27044 (195 views); M27085 (162 views); M27128 (19 views); M27065 (163 views); M27012 (183 views); M27075 (200 views); M26997 (177 views); M27030 (213 views); M27058 (159 views); M27079 (214 views); M27060 (208 views); M27091 (7 views); M27076 (174 views); M27018 (205 views); M26992 (221 views); M27041 (160 views); M27098 (5 views); M27005 (148 views); M27040 (229 views); M27019 (169 views); M27023 (197 views); M27061 (216 views); M26994 (208 views); M27042 (211 views); M27033 (166 views); M27070 (226 views); M27004 (145 views); M27072 (211 views); M27111 (5 views); M27066 (215 views); M38450 (4 views); M27054 (176 views); M27031 (199 views); M27036 (212 views); M27056 (163 views); M27102 (5 views); M27090 (4 views); M27043 (204 views); M27038 (163 views); M27124 (4 views); M27052 (221 views); M27014 (223 views); M27039 (170 views); M27020 (170 views); M27046 (162 views); M27026 (155 views); M27016 (218 views); M27022 (199 views); M27011 (171 views); M27100 (5 views); M27015 (215 views); M27035 (167 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 list10732
    Specimen list63953
    Bibliography565
    Documents list2




    Project downloads

    type number of downloads Individual items downloaded (where applicable)
    Total downloads from project263
    Project downloads261
    Media downloads2M26861 (1 download); M27052 (1 download);