Download Animal Diversity by Diana R. Kershaw (auth.) PDF

By Diana R. Kershaw (auth.)

Show description

Read or Download Animal Diversity PDF

Best zoology books

Grzimek's Animal Life Encyclopedia. Birds 1

V. 1. decrease metazoans and lesser deuterostomes / Neil Schlager, editor -- v. 2. Protostomes / Neil Schlager, editor -- v. three. bugs / Neil Schlager, editor -- v. 4-5. Fishes I-II / Neil Schlager -- v. 6. Amphibians / Neil Schlager, editor -- Reptiles / Neil Schlager, editor -- v. 8-11. Birds I-IV / Donna Olendorf, venture editor -- v.

The Tighty Whitey Spider: And More Wacky Animal Poems I Totally Made Up

It really is reliable: little ones wish extra of Kenn Nesbitt's sidesplitting poetry. they can not get adequate of his shrewdpermanent wordplay, awesome imagery, and zany rhymes. during this brand-new assortment, Kenn has completely made up over fifty poems related to Acrobatic Cats, Kung Fu Pets, and Chickens on desktops.

Population Ecology of Raptors

Dr Newton's booklet is anxious with all features of inhabitants law in diurnal birds of prey, their social behaviour, dispersion, numbers, pursuits, breeding and mortality. He has drawn on his personal reviews in Scotland and on fabric and investigations all over the world to provide an authoritative and stimulating synthesis of present considering and learn at the ecological difficulties of the Falconiformes.

Additional resources for Animal Diversity

Sample text

The larger macronucleus is kidney-shaped with the smaller micronucleus lodged in a depression at one side. The macronucleus controls the ordinary activities of metabolism and growth while the micronucleus is concerned with reproduction. Thus if the micronucleus is removed the animal can survive, but not reproduce. Locomotion The animal moves through the water by beating its cilia, and may also use them to glide over a solid substrate. In slow motion a cilium may be seen to stiffen and bend over rapidly to lie nearly parallel with the body surface.

Each individual is vase-shaped with a central cavity (the paragaster or spongocoele) and a large opening (the osculum) at the opposite end of the attachment (stolon). The sponge wall consists of three layers: an outer pinacoderm; a supporting gelatinous protein matrix, the mesohyal; and an inner feeding layer of choanocytes, which are closely similar to the choanoflagellates. The pinacocytes are highly contractile, and thus the animal is able to increase or decrease in size. Further contract ability is provided in some species by the collenocytes, which have long cytoplasmic strands extending across the spaces through The protozoan ciliates demonstrate the greatest complexity that has evolved in a unicellular organism.

Since sponges have no obvious protective devices and no ability to escape they might be regarded as particularly vulnerable to predators. In fact they are avoided by most potential predators such as fish, since their sharp spicules will penetrate any soft tissue exposed to them and they apparently taste and smell unpleasant. Indeed many small animals, for example crabs, take advantage of this to protect themselves. For example, some small marine sponges are always found in association with hermit crabs.

Download PDF sample

Rated 4.40 of 5 – based on 25 votes