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At least 433 records · Page 24Linked to original sources
PubMed1996

Molecular phylogeny for marine turtles based on sequences of the ND4-leucine tRNA and control regions of mitochondrial DNA.

Marine turtles are divided into two families, the Dermochelyidae and the Cheloniidae. The majority of species are currently placed within the two tribes of the Cheloniidae, the Chelonini and the Carettini, but debate continues over generic and tribal affinities as well as species boundaries. We used nucleotide sequences (907 bp) from the ND4-LEU tRNA region and the control region (526 bp) of mitochondrial DNA to resolve areas of uncertainty in marine turtle (Chelonioidae) systematics. The ND4-LEU tRNA fragment was more conserved than the fragment from the control region, with sequence divergences ranging from 0.026 to 0.148 and 0.067 to 0.267, respectively. Parsimony analysis based only on the ND4-LEU tRNA data suggests that the hawksbill, Eretmochelys imbricata, lies within the tribe Carettni and is closely related to the genus Caretta, but could not resolve the position of the flatback, Natator depressus. A similar analysis based only on the control region sequence data suggested that N. depressus is affiliated with the Chelonini, but failed to resolve the position of E. imbricata and the loggerhead, Caretta caretta. In contrast to these results, the combination of both data sets with published cytochrome b data produced a phylogeny based on 1924 bp of sequence data which resolves the position of E. imbricata relative to Caretta and Lepidochelys and joins N. depressus as sister to the Carettini. Based on the molecular data, the Chelonini contains the Chelonia species, while the Carettini contains the remaining species of Cheloniidae. The control region sequence divergence between Pacific and Atlantic populations of the leatherback, Dermochelys coriacea, was relatively low (0.0081) when compared with the green turtle, Chelonia mydas (0.071-0.074). Atlantic and Pacific populations of Ch. mydas were found to be paraphyletic with respect to the black turtle, Ch. agassizi, suggesting that the current taxonomic designations within the Pacific Chelonia are questionable. This analysis shows the utility of combining sequence data for different regions of mtDNA that by themselves are insufficient to obtain robust phylogenies.

Animals↗
PubMed1982

Morphology and immunocytochemistry of the turtle pituitary gland with special reference to the pars tuberalis.

Examination of pituitaries from young and adult turtles representing four families, reveals that in addition to the abundant juxtaneural pars tuberalis (juxPT) found in this class of reptiles, there is generally a substantial amount of pars tuberalis (PT) tissue closely associated with the pars distalis (PD). The PT forms a cortical layer especially conspicuous around the anterior tip of the PD in some species (Trionyx, Kinosternon, Sternotherus), or it forms a thick dorsal layer of tissue irregularly extending onto the sides of the PD in others (Pseudemys, Chrysemys, Lepidochelys, Chelonia). Immunocytochemical studies using unlabelled second antibody and peroxidase-antiperoxidase reveal that in turtles of all ages, the PT tissue allied with the PD (the PTinterna) is composed primarily of cells containing glycoprotein hormones (FSH, LH and TSH), especially the gonadotropins. The juxPT, however, consists mainly of secretory cells unstained by the antisera tested and includes only a small number of gonadotropes and thyrotropes. Although usually widely distributed in the testudinate adenohypophysis, the great majority of gonadotropes and thyrotropes present in the hatchling are in the PTinterna. It is probable that a concentration of these cells in the PTinterna is widespread among vertebrates. In all turtles examined, lactotropes occur principally in the anterior and ventral part of the PD proper; somatotropes are posterior and dorsal. Corticotropes are concentrated as the lactotropes in the anterior PD, but some are also scattered throughout the posterior half of the gland. Lactotropes, corticotropes, and with a few exceptions, somatotropes, do not occur in PT tissue in the turtle.

Adrenocorticotropic Hormone↗
PubMed1994

Anoxia induces changes in translatable mRNA populations in turtle organs: a possible adaptive strategy for anaerobiosis.

The effects of anoxic submergence (16 h at 15 degrees C) on cellular mRNA contents were assessed in five organs of anoxia tolerant turtles Trachemys scripta elegans. Poly(A)+ RNA was extracted from liver, red and white skeletal muscle, kidney and heart of control and anoxic turtles, as well as from heart and kidney of turtles allowed 24 h aerobic recovery (at 15 degrees C) after anoxia exposure. Poly(A)+ RNA content increased by 30% in white muscle from anoxic turtles relative to control animals but was unchanged by metabolic state in other organs. Extracted mRNA was translated in vitro in a wheat germ lysate system and the 35S-labelled polypeptides that were produced were separated by sodium dodecyl sulphate-polyacrylamide gel electrophoresis. Overall translational activity of the mRNA pool [cpm 35S-methionine incorporated per microgram poly(A)+ RNA] was altered by anoxia exposure in three organs, increasing by 38 and 18% in liver and kidney and decreasing by 42% in red muscle. Anoxia exposure also led to qualitative changes in the protein products that resulted from in vitro translation. Sodium dodecyl sulphate polyacrylamide gel electrophoresis revealed the presence of a novel 19.5-kDa polypeptide in liver of anoxia-exposed animals as well as increased amounts of two other proteins at 28.6 and 79.9 kDa. In heart a new translation product of 26.8 kDa appeared in anoxia, and in kidney a 32.8-kDa polypeptide was produced during the aerobic recovery period after anoxia exposure. Anoxia stimulated the appearance of a 37.5-kDa protein in red skeletal muscle but anoxic red muscle also lost proteins of 40, 32, and 28.2 kDa that were present in aerobic controls. Anoxia exposure did not change the proteins produced by in vitro translation in white muscle. The results suggest that anoxia exposure triggers rapid cellular responses in T. s. elegans that modify translatable mRNA populations in organs, leading to new protein transcripts.(ABSTRACT TRUNCATED AT 400 WORDS)

Adaptation, Physiological↗
PubMed1988

Distribution of Müller cells in the turtle retina: an immunocytochemical study.

Müller cells are the major type of glial cell in the vertebrate retina, and appear to participate in important structural and metabolic functions. Although the morphological features of Müller cells have been extensively studied, their topographic distribution across the retina has not been previously reported. We have used a Müller cell-specific monoclonal antibody, 19-33, to study the distribution of Müller cells in turtle retina. The antibody was obtained during a search for cell type-specific monoclonal antibodies in the rat retina. Immunoblotting studies show that 19-33 reacts with a 58 KDa protein that is present in Müller cells. Immunocytochemical studies with en face sections of turtle retina show that the density of Müller cells is fairly uniform across the retina although there are small regional differences. We estimate that the mean Müller cell density is about 1600 cells mm-2 of turtle retina and that each turtle retina contains about 54,000 Müller cells.

Animals↗
PubMed1996

Characterization of a voltage-dependent L-type calcium channel from rabbit and turtle brain.

The binding of [3H]nitrendipine to membrane preparation from turtle and rabbit brain was studied. A single population of [3H]nitrendipine binding sites was detected in both species. [3H]nitrendipine bound with high affinity to brain membrane from both rabbit and turtle, revealing a significant population of binding sites (K(D) values of 0.55 +/- 0.05 nM and 0.56 +/- 0.04 nM and Bmax values of 122 +/- 11 and 275 +/- 18 fmol/mg of protein, respectively). Displacement studies showed a similar order of potency of various unlabeled ligands against [3H]nitrendipine both in rabbit or in turtle: nitrendipine > nifedipine >or= nicardipine >> verapamil >or= diltiazem. Our results show that a two fold increment of [3H]nitrendipine binding sites exists in the turtle brain respect to the rabbit.

Animals↗
PubMed2006

Polychlorinated biphenyl concentrations, congener profiles, and ratios in the fat tissue, eggs, and plasma of snapping turtles (Chelydra s. serpentina) from the Ohio Basin of Lake Erie, USA.

Concentrations and profiles of polychlorinated biphenyls (PCBs) were determined in three tissues of adult snapping turtles (Chelydra serpentina serpentina) from six locations in the Ohio Basin of Lake Erie to characterize tissue variation and geographic trends. The locations included the Ohio Areas of Concern, i.e., the Ashtabula, Black, and Maumee Rivers; the Ottawa River near Toledo; and two reference sites. Mean total PCBs were greatest in turtles from the Ottawa River followed by the Maumee, Ashtabula, and Black Rivers. All three types of samples-fat tissue (FT), eggs, and plasma-showed the same geographic trend in PCB levels. On a wet-weight basis, mean concentrations ranged from 2,148 to 18,669 ng/g in FT, from 183 to 3,683 ng/g in eggs, and from 18 to 201 ng/g in plasma. Across all sites, total PCB concentrations between the tissues were significantly correlated (0.001 < p < 0.005; Pearson correlation coefficient (r ( P )) was between 0.720 and 0.954). Two distinctly different profiles with respect to relative congener and homologue concentrations were found among the sites. One that included four of the six sites examined was characterized by hexa-chlorobiphenyl (hexa-CB) dominance followed by hepta-CBs, with PCBs no. 138 + 163, 153 + 132 + 105, and 180 being the most abundant congeners. The second profile, specific for turtles from the Ottawa River, was different from the first in that tetra-CBs were the most abundant congeners followed by hexa-CBs. Analysis of variance (ANOVA) indicated significant intertissue differences in the PCB homologue profiles, i.e., FT had a higher percentage of hepta-, octa-, and nona-CBs compared with eggs and plasma, whereas eggs showed a higher percentage of hexa-CBs. At any listed location, FT, eggs, and plasma had the same congener profile. An intertissue distribution of lipid-normalized individual congener concentrations examined by regression analyses revealed significant egg-FT, egg-plasma, and FT-plasma relations for >40 congeners (0.001 < p < 0.05). The distribution ratios determined for these congeners from the slope of the regression lines averaged 1.235 +/- 0.279, 0.430 +/- 0.170, and 0.387 +/- 0.115, respectively. The plasma wet weight-FT lipid-normalized concentration ratios for these congeners averaged 0.012 +/- 0.006. Both egg-FT and plasma wet weight-FT lipid-normalized ratios regressed against log K(ow) showed significant decreases, with increasing log K(ow), indicating greater accumulation of highly chlorinated congeners in FT than in other compartments. The estimated 2,3,7,8-tetrachlorodibenzo-p-dioxin toxic equivalents ranged from 0.007 ng/g at reference sites to 0.060 ng/g at contaminated sites and from 0.099 to 1.992 ng/g in plasma and eggs, respectively. In both plasma and eggs, coplanar-CBs were the major contributors to total toxic equivalents (TEQs). Eggs from all contaminated sites had TEQs that exceeded the lowest observed effect level TEQs proposed for bald eagle chicks, in addition to high SigmaPCB levels at some of these sites, especially the Ottawa and Maumee River sites, indicate potentially increased risk to turtles and possibly other wildlife species inhabiting these ecosystems. Significant correlations of total PCBs and individual congeners between FT, eggs, and plasma indicate that blood sampling can provide a good nonlethal measure of PCB exposure and can be used to monitor environmental contamination.

Adipose Tissue↗
PubMed2001

Organochlorine pesticides, PCBs, dibenzodioxin, and furan concentrations in common snapping turtle eggs (Chelydra serpentina serpentina) in Akwesasne, Mohawk Territory, Ontario, Canada.

Subsamples of eight clutches of common snapping turtle eggs (Chelydra serpentina serpentina) were collected from four sites from the territory of the Mohawk Nation, Akwesasne, on the shore of the St. Lawrence River. Egg contents were analyzed for organochlorine pesticides, polychlorinated biphenyls (PCBs), dibenzodioxins, and furans. The sites were 2 to 13 km downstream from PCB-contaminated landfill sites. Maximum concentrations of total PCBs in snapping turtle clutches were extremely high, and ranged from 2 378.2 ng/g to 737 683 ng/g (wet weight) and are among the highest recorded in any tissue of a free-ranging animal. Similarly, in a pooled sample of eggs from all four sites, the summed concentrations of non-ortho PCBs (n = 6 congeners) was also very high at 54.54 ng/g and the summed dioxin and furan concentrations (n = 11 congeners) was 85.8 ng/g. Sum organochlorine pesticide levels varied from 28 to 2,264 ng/g among the four sites. The levels of PCBs found in turtle eggs exceed concentrations associated with developmental problems and reduced hatching success in snapping turtles and other species and also exceed the Canadian tissue residue guidelines for toxic equivalency concentrations. The extremely high levels of organochlorine contaminants demonstrate the high degree of contamination in the environment in the Akwesasne area.

Animals↗
PubMed2000

Polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs), biphenyls (PCBs), and organochlorine pesticides in yellow-blotched map turtle from the Pascagoula River basin, Mississippi, USA.

Concentrations of polychlorinated-dibenzo-p-dioxins (PCDDs), -dibenzofurans (PCDFs), -biphenyls (PCBs), and organochlorine pesticides were measured in tissues of map turtles collected from two locations in the Pascagoula River drainage of Mississippi, USA. PCBs were most predominant among the organochlorines with a concentration of up to 99 ng/g, wet weight (580 ng/g, lipid weight) in livers. The greatest concentration of PCDDs/DFs of 1.1 pg/g, wet weight (15.76 pg/g, lipid weight) was found in the liver of a male turtle. The measured concentrations of organochlorines were less than those reported for turtles from the Great Lakes Basin and upper St. Lawrence River. PCBs contributed 90-99% of the total estimated 2, 3,7,8-tetrachlorodibenzo-p-dioxin equivalents (TEQs). Particularly, PCB congeners 105, 118, and 156 accounted for 68-80% of the estimated toxic potency of PCBs in turtles.

Animals↗
PubMed2005

Do embedded roadway lights protect sea turtles?

Street lighting on coastal roadways is often visible at sea turtle nesting beaches, and disrupts the nocturnal orientation of hatchlings as they crawl toward the sea. Our objective was to determine whether an alternative lighting system (light-emitting diodes, embedded in the roadway pavement) prevented orientation disruption. Hatchlings at the beach oriented normally when only the embedded lights were on, or when all lighting was switched off. However, turtles showed poor orientation when street lighting was on. Measurements confirmed that street lighting was scattered to the beach, whereas embedded lighting was not. We conclude that embedded lighting keeps the beach dark and thus protects sea turtles. However, on two overcast evenings, lighting ("skyglow") from nearby development, reflected by cloud cover to the beach, weakened hatchling orientation. Thus, both indirect (reflected) and direct sources of lighting negatively impact the turtles.

Animal Migration↗
PubMed2006

What makes them pay? Values of volunteer tourists working for sea turtle conservation.

As charismatic mega-fauna, sea turtles attract many volunteers to conservation programs. This article examines the ways in which volunteers value sea turtles, in the specific context of volunteers working with the Caribbean Conservation Corporation, at Tortuguero, Costa Rica. The complexity of volunteer values is explored using a qualitative approach. In-depth interviews with 31 volunteers were conducted in July of 1999 and 2000. Interviews probed, among other things, interest in sea turtles and their conservation, motives for participating, and the most gratifying parts of their volunteer experience. Results show that volunteers hold multiple and complex values for sea turtles, but particular values dominate. Results have implications for understanding human-environment relations and the emerging study of volunteer tourism. There are also management implications for volunteer programs hoping to attract participants.

Animals↗
PubMed2006

Distorting gene pools by conservation: Assessing the case of doomed turtle eggs.

Sea turtles have a high reproductive output and high mortality at early stages of the life cycle. In particular, many nests are laid below or close to high tide lines, and subsequently large numbers of eggs may be inundated and destroyed. A common conservation procedure is to relocate such doomed eggs to higher ground. This article examines this practice in the light of recent data revealing that some individual turtles tend to nest relatively near the water and others relatively higher up the beach. Discussion is focused on the question of why apparently poor placement of nests has not been selected against. Comparison between the ecology of leatherback and hawksbill turtle nesting beaches suggests that predictability of environmental conditions on the nesting beaches has an important influence on patterns of nest-site selection. Options are outlined for the management of nesting beaches where a high proportion of turtle eggs is subject to destruction by flooding.

Animals↗
PubMed2002

Visual acuity thresholds of juvenile loggerhead sea turtles (Caretta caretta): an electrophysiological approach.

Visual evoked potentials measure dynamic properties of the visual system by recording transient electric responses of neural tissue identified to correspond to a specific visual stimulus, such as light or a striped grid. In this study, visual evoked potentials were used to test the visual acuity of juvenile loggerhead sea turtles (Caretta caretta) in water. Subject animals were fitted with a Plexiglas goggle filled with filtered seawater. Stimuli of black and white striped gratings were presented to the turtles using a slide projector directing an image onto a screen via a rotatable mirror that shifted the striped pattern laterally one-half cycle. Bioelectric activity was collected using a digital averaging computer and subdermal platinum electrodes, implanted under the head scutes directly above the optic nerve and the contralateral optic tectum. To isolate the response signal from the noise, signal averaging techniques were used when collecting visual evoked potentials. The resulting response waveforms included a robust positive-negative compound that was used to track the turtle's response to visual stimulation. Acuity thresholds for these sea turtles, which were derived from linear regressions analysis of the positive-negative compound amplitudes versus stripe size, ranged from 0.130 to 0.215. This acuity level is comparable to other inshore, shallow water marine species.

Age Factors↗
PubMed2003

Accommodation behaviour during prey capture in the Vietnamese leaf turtle ( Geoemyda spengleri).

Vietnamese leaf turtles ( Geoemyda spengleri) were tested for their ability to focus on prey objects at various distances. Accommodation was continuously measured by infrared photoretinoscopy. All animals investigated during this study showed a surprisingly high precision of accommodation over a range of over 30 D. Measured accommodation matched the target distance accurately for distances between 3 and 17 cm. The turtles switched between independent and coupled accommodation in the two eyes. Independent accommodation was observed when the turtles inspected their environment visually without a defined object of interest. Coupled accommodation was only observed during binocular prey fixation. When a turtle aimed at a target, the symmetrical focus of both eyes persisted even if vision was totally blocked in one eye or altered by ophthalmic lenses. This suggests that the eyes were linked by internal neuronal mechanisms. The pupil of the eye responded clearly to changes in ambient light intensity. A strong decrease in pupil size was also observed when the eye was focused on a close target. In this case, the constriction of the pupil probably aids in the deformation of the eye lens during near-accommodation.

Accommodation, Ocular↗
PubMed2005

Anoxia tolerance and freeze tolerance in hatchling turtles.

Freezing survival in hatchling turtles may be limited by ischemic anoxia in frozen tissues and the associated accumulation of lactate and reactive oxygen species (ROS). To determine whether mechanisms for coping with anoxia are also important in freeze tolerance, we examined the association between capacities for freezing survival and anoxia tolerance in hatchlings of seven species of turtles. Tolerance to freezing (-2.5 degrees C) was high in Emydoidea blandingii, Chrysemys picta, Terrapene ornata, and Malaclemys terrapin and low in Graptemys geographica, Chelydra serpentina, and Trachemys scripta. Hatchlings survived in a N(2) atmosphere at 4 degrees C for periods ranging from 17 d (M. terrapin) to 50 d (G. geographica), but survival time was not associated with freeze tolerance. Lactate accumulated during both stresses, but plasma levels in frozen/thawed turtles were well below those found in anoxia-exposed animals. Activity of the antioxidant enzyme catalase in liver increased markedly with anoxia exposure in most species, but increased with freezing/thawing only in species with low freeze tolerance. Our results suggest that whereas oxygen deprivation occurs during somatic freezing, freeze tolerance is not limited by anoxia tolerance in hatchling turtles.

Acclimatization↗
PubMed2006

Physiological responses to freezing in hatchlings of freeze-tolerant and -intolerant turtles.

Freeze tolerance is a complex cold-hardiness adaptation that has independently evolved in a diverse group of organisms, including several ectothermic vertebrates. Because little is known about the mechanistic basis for freeze tolerance in reptiles, we compared responses to experimental freezing in winter-acclimatized hatchlings representing nine taxa of temperate North American turtles, including ones that tolerated freezing and others that did not. Viability rates of hatchlings frozen to -3 degrees C for 72 h ranged from 0 to 100%. Tolerance to freezing was poor in Sternotherus odoratus, Graptemys geographica and Trachemys scripta, intermediate in Chelydra serpentina, and high in Emydoidea blandingii, Chrysemys picta bellii, C. p. marginata, Malaclemys terrapin, and Terrapene ornata, and generally reflected the winter thermal ecology of each taxon. Plasma activity of lactate dehydrogenase (LDH), a novel in vivo index of freeze/thaw damage, corroborated viability assessments and demonstrated that cryoinjury occurred even in surviving turtles. Irrespective of taxon, cryoinjury tended to be higher in smaller individuals and in those having relatively low water contents; however, bases for these associations were not apparent. Screening for certain organic osmolytes that might promote freezing survival by colligatively reducing ice content and limiting cell dehydration showed that the plasma of unfrozen (control) turtles contained small quantities of glucose (1.3-5.8 mmol l(-1)) and lactate (0.6-3.2 mmol l(-1)) and modest amounts of urea (range of mean values for all taxa 8.2-52.3 mmol l(-1)). Frozen/thawed turtles of all taxa accumulated modest amounts of glucose and lactate that jointly raised the plasma solute concentration by 30-100 mmol l(-1). We conclude that organic osmolytes accumulated both before and during freezing may promote survival in species that have evolved a tolerance to freezing, but are not necessarily accumulated for that purpose.

Adaptation, Physiological↗
PubMed1999

The physiology of diving in a north-temperate and three tropical turtle species.

We examined changes in blood gases, plasma ions, and acid-base status during prolonged submergence (6 h) of four aquatic turtle species in aerated water at 20 degrees C. Our objective was to determine whether the temperate species, Chrysemys picta bellii, exhibits greater tolerance to submergence apnea than the tropical species, Pelomedusa subrufa, Elseya novaeguineae, and Emydura subglobosa. Blood was sampled from indwelling arterial catheters for measurements of blood PO2, PCO2, pH, and hematocrit and for plasma concentrations of lactate, glucose, Na+, K+, Cl-, total Ca, and total Mg. The pattern of change was similar in all species: a combined respiratory and metabolic acidosis associated with a marked decrease of blood PO2. The severity of the acidosis developed in the temperate species, however, was significantly less than that of the tropical turtles. Lactate rose significantly and HCO3- fell proportionately in all turtles; changes in other plasma ion concentrations were small but were generally in the directions consistent with compensatory exchanges with other body compartments; i.e., cations (K+, Ca, and Mg increased) and anions (Cl- decreased). The results indicate that hypoxia tolerance is a conserved trait in turtles, even in those that do not experience enforced winter submergence, and that the temperate species may be superior in this capacity because of reduced metabolic rate.

Acid-Base Equilibrium↗
PubMed2001

Physiological responses to supercooling and hypoxia in the hatchling painted turtle, Chrysemys picta.

We investigated physiological responses to supercooling in hatchling painted turtles (Chrysemys picta) which remain in their natal nests over winter and therefore may become exposed to subzero temperatures. These turtles are freeze tolerant but also must rely on supercooling to survive exposure to the lower temperatures occurring in nests during winter. We compared whole-body concentrations of lactate, glucose, glycerol, and ATP in turtles chilled at 0 degrees C, -4 degrees C, or -6 degrees C for 5 days, or at 6 degrees C for 19 days. In a companion experiment, we measured metabolite concentrations in turtles exposed to a hypoxic environment for 1 day, 4 days, or 8 days. Supercooling and hypoxia exposure were both associated with an increase in concentrations of lactate and glucose and a decrease in glycerol concentrations (albeit no change in the ATP pool), suggesting that supercooling induces functional hypoxia. We conclude that hypoxia tolerance may be an important pre-adaptation for surviving exposure to subzero temperatures in hatchling C. picta.

Animals↗
PubMed1999

Comparative analysis of FMRFamide-like immunoreactivity in caiman (Caiman crocodilus) and turtle (Trachemys scripta elegans) brains.

The distribution of FMRFamide (FMRFa)-like peptides in caiman (Caiman crocodilus) and turtle (Trachemys scripta elegans) brains was studied by immunohistochemistry. In both species, distinct groups of FMRFa-like immunoreactive (ir) perikarya were present in the medial septal nucleus, accumbens nucleus, nucleus of the diagonal band of Broca, suprachiasmatic area, lateral hypothalamic area, and periventricular hypothalamic nucleus. A few FMRFa-ir neurons in the hypothalamic area were located in the neuroepithelial cell lining of the third ventricle. FMRFa-ir fibers were scattered in all major areas of the brain, from the olfactory bulbs to the rhombencephalon. They formed dense aggregates in the medial septal area, basal telencephalon, median eminence, and infundibulum, and adjacent to the fourth ventricle. The most obvious difference between the FMRFa-ir systems in caimans and turtles concerned the number of nuclei that contained neurons with this immunoreactivity. Eight such clusters were present in the caiman brain, whereas thirteen clusters were found in the turtle brain. The turtle also displayed scattered FMRFa-ir somata in the anterior olfactory nucleus, striatum, lateral septal nucleus, medial and lateral cortex, medial forebrain bundle, lateral preoptic area, and lateral geniculate nucleus. In the caiman brain, a few FMRFa-ir neurons were noted in the ventrolateral area of the pallial commissure and an even smaller number of ir neurons was found dispersed in the optic tracts. Neither formed nuclear aggregates. The results are compared with those described for other vertebrates.

Alligators and Crocodiles↗