Laws / rules associated with evolution, PL-SQL Programming

LAWS / RULES -

Dollo's Law                     :           Living organisms do exhibit evolutionary irreversibility or evolution is irreversible.

Williston's Law               :           During the evolution of a lineage, serially homologous parts tend to reduce in number but get more and more differentiated and advance in function.

e.g. Trilobites - were having large number of appendages and more or less identical in shape and structure.

Modern arthropods possess fewer appendages but specialized function.

In fish the maximum number of bones in the skull has been counted 150. whereas in mammals only about 28 bones are present.

Cope's rule                     :           Organisms have tendency towards increase in size during their evolution.

E.g., evolution of horse, camel, elephant and all other herbivorous mammals exhibit increase in size. Dinosaurs, Turtle and Tortoise.

Hardy-Weinberg's Law  :            The relative frequencies of various kinds of gene in a large and randomly mating population tend to remain constant from generation to generation in the absence of mutation, selection and gene flow, (i.e., factors affecting gene frequency).

Gloger's Rule                  :           Desert animals are heavily pigmented and are comparatively small in Size.

Rapoport's Rule              :           Species adapted to colder region have wider latitudinal distribution than the species adapted to warmed climates.

Jordon's Rule                 :           Fishes of colder water are larger in size with more vertebra then those living in warmer water.

Bergman's Law               :           Warm blooded animals are larger in size in the colder regions as compared to hotter parts.

Allen's Law                     :           Extremities of the body like tails and ears become smaller in colder areas.

Baldwin effect                 :           Natural selection acts to bring about adaptations, could arise as a direct response to the environment or to the needs of organisms.

Sewall - Wright effect     :           The random changes in gene frequency occurring by chance in small population and not under the control of natural selection are called Sewall-Wright effect.

Bottleneck effect              :           If small deme isolated and restricted in distribution are exposed to random genetic drift resulting in the fixation of certain genes. The changes occurring in the gene ratio is called bottleneck effect. If in this case the gene pool is already limited the population cannot regain its former richness, that may cause extinction.

Posted Date: 10/8/2012 8:52:50 AM | Location : United States







Related Discussions:- Laws / rules associated with evolution, Assignment Help, Ask Question on Laws / rules associated with evolution, Get Answer, Expert's Help, Laws / rules associated with evolution Discussions

Write discussion on Laws / rules associated with evolution
Your posts are moderated
Related Questions
OUT Mode An OUT parameter returns values to the caller of a subprogram. Within the subprogram, an OUT parameter act like a variable. That means that you can use an OUT formal

Need Database Development with Analysis Tools Project Description: I want a database for large governmental and private data sets on one country that can be simply extended t

Create the four tables and populate them with the given data. Answer the following queries in SQL. 1. Get all part-color/part-city combinations. Note: Here and subsequently, the

1. a. Write a trigger that fires when a part's price is updated. The trigger will write a record into a table called PriceUpdates. The record should contain the information of

Restriction in SQL Syntax: SELECT DISTINCT StudentId FROM IS_CALLED WHERE Name = 'Boris' The WHERE clause operates on the result of the FROM clause in analogo

Write SQL queries to solve the following specifications. Include the query AND THE OUTPUT.  A screen dump of the output is acceptable. Show as many rows as you can. A screen dump i

Scope and Visibility The References to an identifier are resolved according to its visibility and scope. The scope of an identifier is that area of a program unit (subprogram, b

write the program for traffic control system with 10 second, 15 secod, and 20 second delay

LOOP Statements The LOOP statements execute a series of statements at multiple times. The loops enclose the series of statements that is to be repeated. The PL/SQL provides typ

Object Types An object type is a user-defined complex datatype which encapsulates the data structure along with the functions and procedures required to manipulate the data. Th