manipulation – Discover-Nature

Beaks or bills? Two interchangeable words naming the horny part of the jaw of a bird. They have numerous uses including gathering food, feeding, preening, and display, and are often used for functions that would be accomplished by arms and hands on other animal species. Let’s take a closer look at their structure and how birds use them for feeding.

Beaks come in a variety of sizes, and most are proportionate to the size of the bird’s head. Two or more of the bones comprising the lower jaw in birds are often fused together, increasing the strength of the overall structure. Birds do not have teeth, allowing the jaw bones to be lightweight, making it easier for a bird to hold its head out in front of its body while flying.

^{Barn owl, Tyto alba, skull showing fused jaw bones by Didier Descouens, Jul 2010}

Beaks are made from bone covered with keratin, a structural protein providing strength and rigidity. Yet beaks have some flexibility which adds to their dexterity when in use. The inner surface of the keratin layer is constantly growing while the outer surface is equally being worn away by use. Both upper and lower jaws are jointed where they attach to the skull, allowing for extended movements including the ability of a bird to open its jaws wider than most other animal species.

^{Great white pelican, Pelecanus onocrotalus, by Craig Adam, Feb 2013; Red-headed woodpecker, Melanerpes erythrocephalus, by Mark Moschell, May 2016; Evening grosbeak, Hesperiphona vespertina, by Fishhawk, Feb 2021}

A beak is specialized for every species depending on diet and food gathering methods. Cone-shaped beaks, found among cardinals, grosbeaks, and finches, can trap, cut, and crush seeds. Scoop-shaped beaks allow skimmers, spoonbills, and pelicans to slide their lower jaw under slippery prey, then catch and hold onto it . Beaks tipped with a chisel-like point are used by woodpeckers probing into crevices in hard materials. Along with a reinforced skull, keratin reinforces the beak’s toughness, standing up to repeated hammering and prying movements.

^{From upper left: Blue-gray gnatcatcher, Polioptila caerulea, by Dave Wendelken, Jul 2023; Pied flycatcher, Ficedula hypoleuca, by Edward Anderton, Jun 2012; Ruby-throated hummingbird, Archilocus colubris, by Mark Moschell, Jun 2019; Great-horned owl, Bubo virgianus, by Kevin Milazzo, Feb 2021}

Narrow tweezer-like beaks, used by gnatcatchers, warblers, and wrens, stab or seize small insects from branches. Wider and flatter tweezer-shaped beaks on purple martins and flycatchers can snatch an insect in flight. Long, slender beaks on hummingbirds are made for sucking nectar from the deep recesses of long, tubular flowers as well as catching tiny insects, such as fruit flies. Sharply pointed, hooked beaks are used by eagles, owls, hawks and shrikes to stab prey and hold on while pulling the meat apart into mouthful-sized chunks.

Many beaks serve more than one feeding function, as species change their diet from one type of food to another as seasons change. Tongues are an important addition to the mouth, manipulating food items for beaks to be more effective. Different sizes and colors of beaks convey information to other individuals about a birds sex and maturity level. This essential body part provides birds with many of the same capabilities as other animal species. Come to the Jurica-Suchy Nature Museum, or a nature center near you, to learn more about the many adaptations of birds.

^{Ruddy Duck, Oxyura jamaicensis, by Sergey Yeliseev, Nov 2013}

Elephants are the largest land mammals and they live in a variety of habitats in tropical and subtropical regions. Their native habitat is often savanna, grassland or forest although they can also be found in desert, swamp, and highlands. These areas get twelve hours of sunlight each day, with warm, daily temperatures averaging from the lower 70s to above 100˚F for animals living in the desert. Heat and gravity are two natural factors that affect all large animals, and elephants have some unique methods and body design to compensate for both.

^{Walking in Kruger National Park by Simone Eman, simoneemanphotos}

Elephants have a massive skeleton with solid bones in their feet, legs, hips, and ribs that provide excellent support for all of their weight. Lots of muscles, both large and small, allow easy movement while still protecting their vital organs. But not all of the bones are solid. The skull is honeycombed throughout, so it is light enough that the neck can support the head and allow for many small and precise movements of the trunk, the ears, and the tusks. The brain is small for an animal of this size, but elephants are quick learners, have an excellent memory, and are one of the smartest animals.

^{Elephant’s foot by sboofek, Getty Images}

^{Elephants foot tread by skynavin, Getty Images}

While small animals, such as ants, can hang on to a vertical surface, elephants require a solid set of legs to stand and walk on. They actually stand on the tips of their toes, located along the front edge of the foot. The center and back of the foot is one large pad behind and under the toes that cushions each step and helps to carry their weight. The large, round flat of the foot spreads the weight evenly over a larger area, and their soles have treads to provide traction on slippery or uneven surfaces.

^{Elephant ears by Harvey Sapir, Pexels}

Heat from the sun, and from the exertion of the muscles performing under the tremendous weight of the body, must be dissipated efficiently. This task is handled by the elephant’s ears, which are very large and very thin. Hundreds of blood vessels run through each ear close to the skin to radiate heat away from the body. The blood, now cooled, can be circulated throughout the body. Skin over the rest of the body is thicker, but there is little to no fat underneath, nor is there any fur or hair covering the outside to trap heat. The skin also has many wrinkles creating much more surface area than smooth skin, allowing more heat to be lost to cooler air and water.

^{Celery anyone…by eugen_z, Getty Images}

An elephant’s trunk is a nose-arm-hand all wrapped into one. They can pick up large and heavy objects as well as being able to manipulate the sensitive tip to grab tiny and delicate objects. To help control the heat, they often will suck in a trunkful of water and using the end of the trunk like a shower head, spray all of the water across their body to wet down and cool off. Similarly, they can snuffle up a load of dust to spray across dry or wet skin to create a coating to help keep away biting insects and provide protection from the sun.

Elephants are built to move easily and efficiently in their environment, and they have several methods and adaptations to deal with their size and the heat. Next week we will discover more about family life and the lands they live in.

The Elephant Trunk

An elephant’s trunk is an amazing body part. It is a 300 pound nose-arm-hand about seven feet long. It contains 50,000 muscles, but no bones or cartilage, making it strong and flexible. A vast array of nerves controls it. Elephants use their trunks for a variety of tasks including:
• smelling an approaching rainstorm from 150 miles away
• locating food by smell including grass, branches, and fruit
• lifting objects up to 400 pounds
• reaching food 20 feet off the ground
• using it as a snorkel when swimming underwater
• using the top and bottom lip to pick up a single seed off the ground
• sucking up to 2.5 gallons of water and squirting it into their mouths
• sucking up water to squirt over their backs to cool off
• curling it around large quantities of food to place in their mouths
• controlling the shape and size of the nostril to modulate sounds
• snorting dirt to spray over their backs
• picking up and throwing objects in defense
• entwining with another’s trunk for a friendly hug

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Bird Beaks

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