In the early s, Roger Penrose introduced new mathematical techniques to solve Einstein's equations where exact answers were unavailable because of asymmetry. In the s, Robert MacArthur and his colleagues invented simple holistic ecological models. His program in population ecology was aimed at bringing community ecology, e.
Before the scientific era, people often made up imaginative stories to explain what they saw in the world. The scientific method changed that by requiring rigorous experimentation to test hypotheses and determine what is real.
With the Theory of Evolution, people are back to making up imaginative stories. The primary advantage of complete metamorphosis is eliminating competition between the young and old. Larval insects and adult insects occupy very different ecological niches.
Whereas caterpillars are busy gorging themselves on leaves, completely disinterested in reproduction, butterflies are flitting from flower to flower in search of nectar and mates.
Because larvas and adults do not compete with one another for space or resources, more of each can coexist relative to species in which the young and old live in the same places and eat the same things. Ultimately, the impetus for many of life's astounding transformations also explains insect metamorphosis: Nevertheless, "biologists have established a plausible narrative about the origin of insect metamorphosis, which they continue to revise as new information surfaces.
In response to this unfavorable situation, some pro-nymphs gained a new talent: If such pro-nymphs emerged from their eggs before they reached the nymphal stage, they would have been able to continue feeding themselves in the outside world.
Over the generations, these infant insects may have remained in a protracted pro-nymphal stage for longer and longer periods of time, growing wormier all the while and specializing in diets that differed from those of their adult selves--consuming fruits and leaves, rather than nectar or other smaller insects.
Eventually these prepubescent pro-nymphs became full-fledged larvae that resembled modern caterpillars. The underside of the wing has a brown pigment, which helps hide the resting blue morpho. That shimmering blue on top is not pigment.
These extremely tiny shapes that cover the scales on top of the wing cause light wave interference. Blue light has a wavelength range from to nm. The slits in the scales of the Morpho are nm apart.
Because the distance between slits corresponds to half of the wavelength of blue light, this is the wavelength that undergoes constructive interference. The slits are attached to a base of melanin, a material that absorbs light, further strengthening the blue image.
If evolutionists get around to making up a story for how these structures evolved, what do you think it will be? Come on, use your imagination! Scallop eyes Quotes from a report in Science journal Scallops possess a visual system comprising up to eyes. The optic nerves from nearly all of the eyes project on to the site of visual processing in scallops.
The following, inevitably incomplete, introductory glossary of terms and concepts links to other topics discussed elsewhere on this site, as well as including general topics of interest such as well-known prehistoric animals. CHROMOSOMES; They are fine threads made up of DNA and proteins compacted into genetically strong threads called chromosomes, for they give color when stained acetocarmine or fuchsin. Aug 09, · Meiosis is a reduction division that occurs in the gonads to produce egg and sperm cells while Mitosis is a process in which nuclear material is exactley riplicated. Anonymous · 1 decade ago 0Status: Resolved.
There, the scallop can combine the visual information from the Two striking features were observed in all the eyes. First, the mirror does not have a simple hemispherical shape. Rather, the curvature of the mirror varies across its surface.
Second, the optical axes of the mirror and the lens are not aligned. The crystals are arranged so that the high-refractive-index faces are oriented toward the direction of the incident light across the mirror, creating a highly reflective surface.
The square-plate morphology is also optimized for tiling.
The multilayered mirror is constructed from 20 to 30 layers of crystals separated by thin layers of cytoplasm. Crystal tiling minimizes surface defects at the crystal interfaces that would cause optical diffraction effects. The mirror forms images on a double-layered retina used for separately imaging the peripheral and central fields of view.
The mirror forms functional images on both retinas, which appear to be specialized for different functions. The distal retina responds to relatively dark, moving features, triggering defense or escape reflexes. The image-forming mirror in the eye of the scallop. Cuttlefish skin Cuttlefish have "one of the most complex systems of motor coordination ever recorded.
If the radial muscles that control a chromatophore are relaxed, the pigments are imperceptible. But muscle contraction produces a colorful pixel several tens of micrometres wide.
Cuttlefish transfix their prey by strobing as they approach. The pigment of every chromatophore starts as yellow before turning red, then brown, and ending up as black. New chromatophores are generated throughout the life of the cuttlefish, and the ratio of black to colored chromatophores is maintained by keeping a tight balance between the birth rate of new cells and the time it takes them to mature to a black color.
This process involves sets of muscles called papillae that create bumps and lumps.Cell division ∑ - Understandings: ∑ - Mitosis is division of the nucleus into two genetically identical daughter nuclei. During cell division (mitosis and cytokinesis) the cell divides into two genetically identical daughter cells.; During S phase in the cell cycle, the cell will replicate its chromosomes to create to identical sets of chromosomes (now called chromatids) attached in.
Spermatogenesis is the process of forming sperm cells by meiosis (in animals, by mitosis in plants) in specialized organs known as gonads (in males these are termed testes).
After division the cells undergo differentiation to become sperm cells.
The 'lampbrush' phase of extended chromosomes during meiosis has also been suggested to enable forms of genetic re-processing. In non-mammals this extended phase involves open transcription of coding and non-coding regions and has been proposed to be a form of genetic processing (Wolfe R), which probably occurs in a less obvious way in mammals as well.
An organism needs mitosis when the cells in the organism divide and grow. Meiosis is needed for the sex cells in the organism for reproductive purposes. For example, eggs and sperms need meiosis. Feb 03, · If meiosis didn't happen, organisms couldn't reproduce, and if mitosis didn't occur, organisms would die because cells undergo cellular respiration in order for us to even breathe!
Source(s): benny s · 1 decade agoStatus: Resolved. An organism needs mitosis when the cells in the organism divide and grow. Meiosis is needed for the sex cells in the organism for reproductive purposes.
For example, eggs and sperms need meiosis. Meiosis increases the genetic variation which allows for evolution and the adaptation of .