• Origin                                                                                                          
                          • Tree that orignates the proto annelid from the ancestoral cock roach. As you can see the formations of the other species.
                          •             Tree
                              • Tree for specific cock roach. this tree describes the specific types of offspring of the family within the cock roach species. 
                              • Source:                                                                                   
                                • This article depicts how the earth first began with a series of steps which evolved into organisms. The beginning of the article starts with the primordial soup, which were microbes in the ocean bed. Second the electricity from the atmosphere which was demonstrated by miller Urey experiment. Electric Spark, which was thought to be the building blocks of the early earth. Community Clay section of this article tells how the clay provided organic material for organisms can correlate with the organisms that lived in this era. This also includes the ocean deep vents and ice ages which provided the earth to cool to reform. Finally rna described to depicts the portion which proteins pre genetic translation and transcription to lead to organelle complex in mechanisms.

  • Diversity of Prokaryotes
    •  Source:,

      Images from the article below.                           

Kingdom : Metazoa

Subkingdom: Eumetazoa

Division : Bilateria

Grade : Eucoelomata

Phylum : Arthopoda

Class : Insecta

Order : Orthoptera

Family : Blattidae

Genus : Periplaneta

Species : americana

external view of cockroach


External Features : Perplaneta americana is one of the several species of cockroaches that inhabit our country. Generally cockroaches are among the most common house hold insects.

Cockroach is a nocturnal, omnivorous animal. It feeds on any kind of organic matter.

Cockroach has a dorso ventrally flat, compressed body which is covered by a hard, chitinous exoskeleton. It is in the form of separate plates. The dorsal plate is called tergum and the ventral plate is called sternum. Laterally the plates are joined by pleura.

The segmented body is divided metamerically into segments. Three regions can be recognised in the body, namely a head, a thorax and an abdomen.

The head is a region formed by the fusion of six embryonic segments covered by very hard exoskeletal plates called sclerites. The head is triangular in shape and it is held at right angles to rest of the body. The head bears a pair of compound eyes, a pair of antennae, a mouth terminally and a group of appendages collectively known as mouth parts (trophi).

The Thorax is formed by three independent segments : prothorax, mesothorax and metathorax. Each thoracic segment bears a pair of walking legs on the ventral side. Dorsally, the mesothorax and the metathorax bear each, a pair of wings. The anterior pair of wings, called forewings are used as wing covers for the posterior pair of wings called hindwings, which are used for flight


    •  Article _
    •  Image from the article above.

      Info of the article: This article illustrates how early organism of the arthropod known as Fuxianhuia protensa found in the China's Yunnan Province was suspected to have a complex yet intelligent characteristics of pre early to what we know as cock roach. These characteristics were believed to be alive 520 Million years ago that the insects would have a brain that would evolve later around 20 million years. The fossil shown above shows a nervous system in the fossil where the brain material is dark and iron rich mineral traces that was found by the Uppsala University of Earth of Science. Three optic neuropils that connected in the nerve fiber which would bring controversy as scientists believe that the true origin were that of the family sub species, daphnia from the modern day insects called Fuxianhuia

    • Info of biological notes:  
    • Describes the main multicellular groups that we see today are:

      • Animals

      • Fungi

      • Green algae, including plants

      • Red and brown algae

    • Evolution of early Multicellularit evolution wasw suspected to that the early life form lacked hard tissue, where they have been distoreted or destroyed over time. 

  • Evolution of Plants and Animals

    • Info Article: This article explains how the National Evolutionary Synthesis Center describes how the natural selection and representing 100 species of varies species to grow in size for the earlier season timing for early breeding proliferation. These increase in size are explained using the Goldilocks model or opposing how well adapted the organisms to be not too large or not too small but just right for the condition of how plants and animal can show symbiosis of the earth to allow organisms survival.
      1. Joel G. Kingsolver, Sarah E. Diamond. Phenotypic Selection in Natural Populations: What Limits Directional Selection? The American Naturalist, 2011; 177 (3): 346 DOI: 10.1086/6583
  • Evolution of Developmental Pathways
    • Article above talks about the evolutionary histrory of the blatodea, cockroaches, its introduction provides information regarding its survival of at least 250 million years and more.  
Discuses how cockroaches eating habits, its favorable condition and its physiological identity. 


Species Level Variation
Description: Map that shows state in beige show the preferred location for the American cockroaches to live. This would suggest the climate and human population that the cockroach favors.
Population variation of the american cockroach.This picture shows the geographic variants of the same type of cockroach.

Evolutionary Force
Selective Force:

Restriction of Selection within Variability

Repeatability of standard metabolic rate and gas exchange characteristics in a highly variable cockroach, Perisphaeria sp.

  1.                                                                                                                  Elrike Marais and 
  2. Steven L. Chown*

Selective force:  
The natural selection force theory needs a sort of variation in order to thrive under a variety of conditions. The article tells how the cockroackes are able to adapt by their metabolic mechanisms. There ability to intake carbon dioxide, sulfuric acid, oxygen, carbon shows how diverse the ability to intake energy. The Natural selection in this case would have to believe that its not the size of the organism but there traits as they evolve over time to maintain a stable survival rate.


Figure Above
Gas exchange patterns shown by Perisphaeria sp. (Blattodea, Blaberidae). (A) Gas exchange during activity, (B) Continuous gas exchange pattern, (C) Discontinuous gas exchange cycle pattern, (D) Interburst–Burst pattern, (E) Pulsation pattern. In each case, CO2 is shown as the lower curve (left axis) and activity as the upper curve (right axis). Activity is interpreted as the variance of activity about the mean value, rather than the absolute value of this activity. It is negligible except in the case of A.

Additional Summary
For natural selection to take place several conditions must be met, including consistent variation among individuals.selection is likely to act on the trait of an animal of a given size, rather than on the residual variation of that trait once size has been accounted for, size correction is inappropriate.metabolic rate, and cyclic gas exchange and its components were examine. Showed the acceptibility of co2 and o2 and results provide strong evidence that one of the conditions for considering natural selection an important process in the evolution both of gas exchange traits and standard metabolic rate


Dynamics of Aggregation and Emergence of Cooperation


  Universite´ Libre de Bruxelles, Unit of Social Ecology, CP 231. B-1050 Brussels, Belgium

 Through experimental and theoretical studies, we show how a single behavior—the resting time—leads to a collective choice in both species. This behavior is a response to the density of conspecifics and can also be modulated by heterogeneities in the environment.In cockroaches, it allows the gathering of individuals in particular shelters, depending on the proximity between strains. These results are discussed with emphasis on the role of aggregation processes in the emergence of cooperativity and task allocation. In cockroaches, the unique modulated parameter contrasts with the different patterns. The shift between aggregation and segregation is obtained without any behavioral modification, such as the introduction of aggressive behavior.


Figure 4.
Experimental distribution of the proportion of cockroach larvae present in shelter this graph shows how the shelter from 80-100 percent of the cockroach population aids for the favor of 0-19% help with stranger cockroach kept larvae in shelter and how 80-100% shows in the experimental how cockroaches who are related help the larvae shelter.


Behavioral and Physiological Ecology and Community 

Structure of Tropical Cockroaches

Coby Schal

Mechanisms for interference competition in cockroaches involve agonistic interactions yet such contests for perches. Interspecific and intrasexual encounters on foliage most commonly resulted in avoidance behavior,except when naturally or experimentally baited with food. However for mating, the male cockroaches would partner with a female or gather food for the female in order to mate. Beneficial for the fitness within a given area which would allow the cockroach to pass offspring. pg. 67

 Species Defined 
Phylogeny of cockroaches and related insects based on DNA sequence of mitochondrial ribosomal RNA genes
Srinivas Kambhampati

This article defined the cockoaches relationship between their own species  by means of its phylogeny body structure based on the number and size of the segments of the insect. In the Cryptocecercus puntulatatus (cockroach) based on its Dna sequence of mitochondrail rRna genes.


Hybridization studies on Blattella germanica and Basahinai (Dictyoptera: Blattellidae): Species divergence and a possible influence of a major chromosome mutation

Mary H. Ross

     A study of Blattella  a non-reciprocal translocation that apparently involved the transfer of the nucleolus organizing region from the X chromosome  to chromosome B.asahinai. Continued study on divergence of the two species included genetic analyses of fecundity, egg case hatch, nymphal hatch, sex ratios, and segregation of X chromosomes and the segment carrying the Basahinai nucleolar organizing region in interspecific and backcross matings. Overall, a complex of maternally related disadvantages and possible effects of X chromosome – cytoplasmic interactions. 

Key Evolution


The key is certain neurons that signal the brain about foods.

Image Description: This image made from video provided by Ayako Wada-Katsumata shows glucose-averse German cockroaches avoiding a dab of jelly, which contains glucose, and favoring the peanut butter. For 30 years, people have been getting rid of cockroaches by setting out sweet-tasting bait mixed with poison. But in the early 1990s, a formerly effective product stopped working. Some cockroaches had lost their sweet tooth, rejecting the corn syrup meant to attract them. Later studies showed they were specifically turned off by the sugar glucose in the syrup

Source Image&article :

Rapid mutation  for the glucose aversion may have arisen in an individual cockroach in response to bait. Or it may have already been present in just a few individuals when the arrival of the bait suddenly gave them an advantage for surviving and reproducing. Their offspring would inherit the trait and increasingly replace other cockroaches. Key genes that are produced from the nuerons of these cockroach could influence their behavior towards scents or attractions for survival.

Humans Interaction

Why Cockroaches Stay in Your Neighborhood

cockroach specimen that was mailed to his lab for DNA testing.


New research shows the insects tend to stay in the neighborhoods they grew up in and segregate themselves, much like the city's ethnic groups and income classes.

Example of Evolution

Description: Map that shows state in beige show the preferred location for the American cockroaches to live. This would suggest the climate and human population that the cockroach favors.

Cockroaches & Humans

As far as an evolutionary similarity in cockroaches and humans are limited to none. However the changes at which cockroaches does to humans have a much greater impact such as the cleanliness of the individual living with cockroaches since cockroaches are an opportunistic creatures if the lifestyle of the individual consistently increase in habit living would increase in the population of the cockroach to proliferate. 

These increase in population would cause allergic reactions higher risk of asthma in young infants and harmful to the respiratory system in humans. Thus cockroaches aid in the economy by created jobs that would exterminate these cockroaches and limit the amount of population in a giving area. 
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How Do Cockroaches Affect Health?

Cockroach allergens behave like dust mite allergens and stick to heavier particles that quickly settle. These allergens do not remain airborne for long. Activities like vacuuming may stir up allergens that have settled in dust or fabrics. The most common way to inhale cockroach allergen is to breathe in dust or allergens that have collected in pillows, bedding or other dust-trapping fabrics. 1

Not only do cockroach allergens trigger asthma and allergies, researchers are exploring evidence that early exposure to cockroach allergen can actually cause asthma to develop in preschool aged children.1 Inhaling particles from cockroaches can cause coughing and wheezing in babies less than 12 months of age. 2

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