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Melanism: Evolution in Action

Melanism: Evolution in Action is a book by Dr. Mike Majerus, published in 1998. It is an update of Bernard Kettlewells book The Evolution of Melanism. The book contains a very useful summary of Majerus work on melanism in ladybirds and a review o ...

                                               

No Struggle for Existence, No Natural Selection

No Struggle for Existence, No Natural Selection: A Critical Examination of the Fundamental Principles of the Darwinian Theory is a 1908 book by George Paulin. Paulin argues in the book that there is no struggle for existence in nature and that al ...

                                               

Only A Theory

Only A Theory: Evolution and the Battle for Americas Soul is a 2008 book by the American cell biologist and Roman Catholic Kenneth R. Miller. In the book, Miller examines the battle between evolution and intelligent design, and explores the impli ...

                                               

The Selfish Genius

The Selfish Genius: How Richard Dawkins Rewrote Darwins Legacy is a 2009 book by Fern Elsdon-Baker about the history of evolutionary theory, published to coincide with the 150th anniversary of the publication of Charles Darwins On the Origin of S ...

                                               

The Theory of Evolution

The Theory of Evolution is a book by English evolutionary biologist and geneticist John Maynard Smith, originally published in 1958 in time for 150th anniversary of the birth of Charles Darwin and the centenary of the publication of The Origin of ...

                                               

Cursorial

A cursorial organism is one that is adapted specifically to run. An animal can be considered cursorial if it has the ability to run fast or if it can keep a constant speed for a long distance." Cursorial” is often used to categorize a certain loc ...

                                               

Stylophthalmine trait

The Stylophthalmine trait is an adaptation present in the larvae of several different species of actinopterygian fish. It is characterised by the development of elliptically shaped eyes, which are situated at the apex of long periscopic stalks ex ...

                                               

Arthropod gap

The arthropod gap is an apparent gap in the arthropod fossil record used in the study of evolutionary biology. It still occurs in the early Carboniferous, coinciding and extending past the Romers gap for tetrapods, which may have been caused by l ...

                                               

Rate of evolution

The rate of evolution is a variable of considerable interest in evolutionary biology. It concerns the limits of adaptation to natural environments as well as the limits of artificial selection.

                                               

Law of Life

The Law of Life is a term coined by author Farley Mowat in his 1952 book People of the Deer, and popularized by Daniel Quinn, to denote a universal system of various natural principles, any of which tend to best foster life - in other words, any ...

                                               

Becklin–Neugebauer Object

The Becklin–Neugebauer Object is an object visible only in the infrared in the Orion Molecular Cloud. It was discovered in 1967 by Eric Becklin and Gerry Neugebauer during their near-infrared survey of the Orion Nebula. The BN Object is thought t ...

                                               

Embedded cluster

Embedded stellar clusters, or simply embedded clusters, are open clusters that are still surrounded by their progenitor molecular cloud. They are often areas of active star formation, giving rise to stellar objects that have similar ages and comp ...

                                               

Horsehead Nebula

The Horsehead Nebula is a small dark nebula in the constellation Orion. The nebula is located just to the south of Alnitak, the easternmost star of Orions Belt, and is part of the much larger Orion Molecular Cloud Complex. It appears within the s ...

                                               

Infrared dark cloud

An infrared dark cloud is a cold, dense region of a giant molecular cloud. They can be seen in silhouette against the bright diffuse mid-infrared emission from the galactic plane.

                                               

SSPSF model

The SSPSF model of star formation was proposed by Mueller & Arnett in 1976, generalized afterward by Gerola & Seiden in 1978 and Gerola, Seiden, & Schulman in 1980. This model proposes that star formation propagates via the action of shock waves ...

                                               

T Tauri wind

The T Tauri wind - so named because of the young star currently in this stage - is a phenomenon indicative of the phase of stellar development between the accretion of material from the slowing rotating material of a solar nebula and the ignition ...

                                               

Bat wing development

The order Chiroptera, comprising all bats, has evolved the unique mammalian adaptation of flight. Bat wings are modified tetrapod forelimbs. Because bats are mammals, the skeletal structures in their wings are morphologically homologous to the sk ...

                                               

List of soaring birds

This is a list of soaring birds, which are birds that can maintain flight without wing flapping, using rising air currents. Many gliding birds are able to "lock" their extended wings by means of a specialized tendon. Bird of prey Secretary bird H ...

                                               

Hypuronector

Hypuronector is a genus of extinct drepanosaur reptile from the Triassic Period that lived in what is now New Jersey. The etymology of the name translates as "deep-tailed swimmer from the lake", in reference to its assumed aquatic habits hypothes ...

                                               

Insect flight

Insects are the only group of invertebrates that have evolved wings and flight. Insects first flew in the Carboniferous, some 350 million years ago. Wings may have evolved from appendages on the sides of existing limbs, which already had nerves, ...

                                               

Microraptor

Microraptor is a genus of small, four-winged paravian dinosaurs. Numerous well-preserved fossil specimens have been recovered from Liaoning, China. They date from the early Cretaceous Jiufotang Formation, 120 million years ago. Three species have ...

                                               

Insect wing

Insect wings are adult outgrowths of the insect exoskeleton that enable insects to fly. They are found on the second and third thoracic segments, and the two pairs are often referred to as the forewings and hindwings, respectively, though a few i ...

                                               

Fin and flipper locomotion

Fin and flipper locomotion occurs mostly in aquatic locomotion, and rarely in terrestrial locomotion. From the three common states of matter - gas, liquid and solid, these appendages are adapted for liquids, mostly fresh or saltwater and used in ...

                                               

Brachiation

Brachiation, or arm swinging, is a form of arboreal locomotion in which primates swing from tree limb to tree limb using only their arms. During brachiation, the body is alternately supported under each forelimb. This form of locomotion is the pr ...

                                               

Vertical clinging and leaping

Vertical clinging and leaping is a type of arboreal locomotion seen most commonly among the strepsirrhine primates and haplorrhine tarsiers. The animal begins at rest with its torso upright and elbows fixed, with both hands clinging to a vertical ...

                                               

Akidolestes

Akidolestes cifellii is a genus of spalacotheriid mammal preserved with a complete post-cranium and a partial skull has been discovered from the Yixian Formation of Liaoning, China. The holotype of Akidolestes cifellii is reserved in Nanjing Inst ...

                                               

Concertina movement

Concertina movement is the movement occurring in snakes and other legless organisms that consists of gripping or anchoring with portions of the body while pulling or pushing other sections in the direction of movement.

                                               

Crawling (human)

Crawling or quadrupedal movement is a method of human locomotion that makes use of all four limbs. It is one of the earliest gaits learned by human infants, and has similar features to four-limbed movement in other primates and in non-primate qua ...

                                               

Digitigrade

A digitigrade is an animal that stands or walks on its digits, or toes. Digitigrades include walking birds, cats, dogs, and many other mammals, but not plantigrades or unguligrades. Digitigrades generally move more quickly and quietly than other ...

                                               

Effect of gait parameters on energetic cost

The effect of gait parameters on energetic cost is a relationship that describes how changes in step length, cadence, step width, and step variability influence the mechanical work and metabolic cost involved in gait. The source of this relations ...

                                               

Facultative bipedalism

A facultative biped is an animal that is capable of walking or running on two legs, as a response to exceptional circumstances, while normally walking or running on four limbs or more. In contrast, obligate bipedalism is where walking or running ...

                                               

Gait

Gait is the pattern of movement of the limbs of animals, including humans, during locomotion over a solid substrate. Most animals use a variety of gaits, selecting gait based on speed, terrain, the need to maneuver, and energetic efficiency. Diff ...

                                               

Lower-limb walking pattern

The function of the lower limbs during walking is to support the whole-body against gravitational forces while generating movement patterns which progress the body forward. Walking is an activity that is primarily confined to the sagittal plane, ...

                                               

Petrolacosaurus

Petrolacosaurus is an extinct genus of diapsid reptile from the late Carboniferous period. It was a small, 40-centimetre long reptile, and the earliest known reptile with two temporal fenestrae. This means that it was at the base of Diapsida, the ...

                                               

Plantigrade

In terrestrial animals, plantigrade locomotion means walking with the toes and metatarsals flat on the ground. It is one of three forms of locomotion adopted by terrestrial mammals. The other options are digitigrade, walking on the toes with the ...

                                               

Quadrupedalism

Quadrupedalism is a form of terrestrial locomotion in animals using four limbs or legs. An animal or machine that usually moves in a quadrupedal manner is known as a quadruped, meaning "four feet". The majority of quadrupeds are vertebrate animal ...

                                               

Rectilinear locomotion

Rectilinear locomotion or rectilinear progression is a mode of locomotion most often associated with snakes. In particular, it is associated with heavy-bodied species such as terrestrial pythons and boas, although most snakes are capable of it. I ...

                                               

Sidewinding

Sidewinding is a type of locomotion unique to caenophidian snakes, used to move across loose or slippery substrates. It is most often used by the Saharan horned viper, Cerastes cerastes, and the sidewinder rattlesnake, Crotalus cerastes, to move ...

                                               

Transition from walking to running

Human locomotion is considered to take two primary forms: walking and running. In contrast, many quadrupeds have three distinct forms of locomotion: walk, trot, and gallop. Walking is a form of locomotion defined by a double support phase when bo ...

                                               

Unipedalism

The term uniped refers to a person or creature with only one foot and one leg, as contrasted with a biped and a quadruped. Moving using only one leg is known as unipedal movement. Many bivalvia and nearly all gastropoda molluscs have evolved only ...

                                               

Macneills road indicator

Macnaills Road Indicator was a dynamometer for ascertaining the force necessary to draw a carriage over different kind of roads and pavements. It was developed by John Benjamin Macneill in the late 1820s.

                                               

NER Dynamometer Car

The North Eastern Railway Dynamometer Car is a preserved railway dynamometer car. Originally built in 1906 by the North Eastern Railway at Darlington Works, its role was to scientifically measure the performance of trains in order to effect impro ...

                                               

Water brake

A water brake is a type of fluid coupling used to absorb mechanical energy and usually consists of a turbine or propeller mounted in an enclosure filled with water. As the turbine or propeller turns, mechanical energy is transferred to the water ...

                                               

Kinetics (physics)

In physics and engineering, kinetics is the branch of classical mechanics that is concerned with the relationship between motion and its causes, specifically, forces and torques. Since the mid-20th century, the term "dynamics" has largely superse ...

                                               

Born rigidity

Born rigidity is a concept in special relativity. It is one answer to the question of what, in special relativity, corresponds to the rigid body of non-relativistic classical mechanics. The concept was introduced by Max Born 1909, who gave a deta ...

                                               

MacCullagh ellipsoid

The MacCullagh ellipsoid is defined by the equation: x 2 A + y 2 B + z 2 C = 2 E, {\displaystyle {\frac {x^{2}}{A}}+{\frac {y^{2}}{B}}+{\frac {z^{2}}{C}}=2E,} where E {\displaystyle E} is the energy and x, y, z {\displaystyle x,y,z} are the compo ...

                                               

Poinsots ellipsoid

In classical mechanics, Poinsots construction is a geometrical method for visualizing the torque-free motion of a rotating rigid body, that is, the motion of a rigid body on which no external forces are acting. This motion has four constants: the ...

                                               

Bump steer

Bump steer or roll steer is the term for the tendency of the wheel of a car to steer itself as it moves through the suspension stroke. It is typically measured in degrees of steer per metre of upwards motion or degrees per foot. On modern cars th ...

                                               

Scrub radius

The scrub radius is the distance in front view between the king pin axis and the center of the contact patch of the wheel, where both would theoretically touch the road. It could be positive, negative or zero. The kingpin axis is the line between ...

                                               

Steering

Steering is the collection of components, linkages, etc. which allows any vehicle to follow the desired course. An exception is the case of rail transport by which rail tracks combined together with railroad switches provide the steering function ...