User:Santana navarrette

Creationism vs. Science - debate database

Credit: Santana Navarrette

Ongoing Research on Abiogenesis

Organic chemical reactions causing subtle, nuanced morphological and chemical property changes that could have been influenced by surrounding environmental conditions under the presence of self catalyzing oligonucleotide polymers and self-replicating fatty acid micelles leading to the formation of interlinked chemical processes that are self sustaining as long as there are energy sources nearby, such as heat, to influence and catalyze the reactions is infinitely more plausible than "magical god-poofing" in respect to how life arrived on Earth.

Alligator Tool Use

Turns out the crocodile can be a shrewd hunter himself. A University of Tennessee, Knoxville, researcher has found that some crocodiles use lures to hunt their prey.

Allopatric Speciation Explanation

A vicariant isolation of two populations of the same species will cause the two separated population's differential reproductive patterns to be subjected to widely differing selective parameters based on the differing environments and niches they are now independently living in. The halting of gene flow and genetic dispersal between the two populations ensures that the two populations undergo their own specific allele frequency changes. This phenomenon is known as allopatric speciation via cladogenesis.

Altruistic Behavior in Plants

A species of plant, the Impatiens pallida (yellow jewelweed), was used in a study to see if plants had kin recognition, and if so, how they reacted to recognizing a family member in close proximity.

Yellow jewelweed is found in the understory of forests, where light may be scarce but the soil is usually nutrient-rich. Because light is the limiting factor for plant growth in this environment, a plant competing with its neighbors would be most likely to allocate resources to leaves, to be able to get more sunlight, with more leaves.

So; in the scenario with the jewelweed and a "stranger species", the available light was reduced, in order to obtain and measure the plants' responses to the cue for competition. The plant allocated more resources to leaves, as expected, in order to have more surface area for sunlight "collection." By moving their resources into leaves, these plants not only positively affected their own growth by enhancing their ability to acquire a limited resource but also negatively affected their competitors' growth by shading nearby plants and decreasing the competitor's light acquisition abilities....

Now; in the scenario with the jewelweed and a family member, the available light was reduced, in order to obtain and measure the plants responses to the cue for competition. This time, however, the plants did not increase resource allocation to roots or leaves. Rather, they altered their aboveground morphology by increasing stem elongation and branching. Which, although didn't cause as much extra sunlight obtainment, it also didn't negatively effect their neighbors as much....

This almost seems as if it is altruistic behavior in plants. In the presence of kin, the plant used an alternate method to collect more sunlight, even though it is a less effective method. This method so happened to cause less negative effects on neighboring plants at the same time....It helped the neighbors, but didn't help the individual itself....

Ancient Dinosaur Proteins Show Molecular Relationships to Birds

The hypothesis that Avialans are a specialized subset of theropod dinosaur, and are thus an evolutionary divergence from them, is widely accepted amongst paleontologists and biologists.

Another interesting piece of evidence for this relationship is subtlety hidden in a discovery that creationists themselves think helps their position that the earth is only 6,000 years old. They often bring up Mary Schweitzer's discovery of intact dinosaur osteocytes as evidence of a young Earth, because they like to assert that she found "soft, pliable and flexible blood vessels in a supposedly 68 million year old T-Rex fossil".

Now; what they fail to mention is that to revert these osteocytes back to their soft and pliable states, she had to demineralize the fossils by soaking them in ethylenediaminetetraacetic acid for two weeks , and then from there, was able to conduct her experiments on them.

Now that we got the "found soft blood vessels" nonsense out of the way, we can get to the really interesting part (creationists also leave this part of her research out when they bring it up).

When Dr. Schweitzer's set out to see if there was any evidence of DNA and proteins left in the vessels, she used a wide range of independent methods, like any good scientist would do. One of these methods was an immunological approach. By using certain antibodies that are known to bind to certain epitopes, scientists can test to see if certain proteins are present in a specimen or not. A monoclonal antibody is an antibody that only binds to one specific epitope, and is thus highly specific and thus highly useful when searching for specific proteins.

Now, with that in mind, Dr. Schweitzer decided to use a monoclonal antibody called OB7.3, which is specific for avian osteocytes and does not bind to non-avian osteocytes . She knew that because phylogenetic analyses supported the hypothesis that non-avian dinosaurs are related to birds, that this relationship would most likely be found at the molecular level as well. So she thought that this avian specific antibody would also bind to any protein remnants found in the dinosaur specimen as well.

Lo and behold, upon subjecting the dinosaur specimen to the avian specific OB7.3 antigen it was shown to bind, just like it does in modern day avialans. It is a reasonable assumption, and is actually expected, that the specific epitope for this avian-specific antigen would be conserved exclusively between birds and dinosaurs, but not in other taxa, under the model developed by evolutionary theory, but this fact makes no sense using creationism other than saying "that's just the way it is".

Mary completely disagrees with claims about the fossils having to be young in order for this preservation to occus, and has conducted research into the likely reasons for the preservation of the molecule and osteocyte remnants, which never included them being less than 60 million years old.

Mary and her team discovered that haemoglobin-induced solution hypoxia coupled with iron chelation drastically increases the stability of tissues post-mortem. Meaning that tissues preserved in the presence of blood have been shown to remain intact to a much higher degree than tissues preserved without blood, due to the haemoglobin and the iron in blood acting as a natural type of formaldehyde.

Haemoglobin (HB) was chosen to test its preservation properties for four reasons: (i) HB is in known to be bacteriostatic; (ii) in the presence of dioxygen, HB produces free radicals; (iii) blood vessels fill with large amounts of HB after death as red cells begin to die and lyse, thus it is naturally present in large vertebrates; and (iv) heme released from HB, when degraded, will release iron, possibly accounting for the iron particles that have been commonly associated with the ancient preserved soft tissues.

The HB preservation method was shown to increase tissue stability in osteocytes by more than 200-fold, as the HB-treated vessels have remained intact for more than 2 years at room temperature with virtually no change, while control tissues were significantly degraded within 3 days. A stunning effect on tissue stability indeed.

Couple this HB fixation process with the facts that:

(i) Osteocytes are usually inaccessible to other cells, so they are immune from phagocytosis and bacterial attacks post mortem; (ii) Osteocyte cells are inherently resistant to degradation due to their position inside the bone matrix causing an inhibition to cell division. (iii) Osteocytes express apoptotic repressor proteins; and (iv) Osteocytes have very limited access to novel oxygen due to their position inside the bone matrix ...

and we can expect this 200-fold increase in tissue stability to increase dramatically.

Archaeopteryx

A transitional fossil is any fossilized remains of a life form that exhibits traits common to both an ancestral group and its derived descendant group. Using this, we would expect to find transitional fossils in between dinosaurs and birds, and easily enough there are plenty. My favorite evolutionary transition is the transition from theropod dinosaur to bird.

And my favorite "transitional form" in this evolutionary chain is Archaeopteryx - A dinosaur to bird evolutionary link.

--Here's SOME of Archaeopteryx's reptilian features:

Premaxilla and maxilla are not horn-covered.

Trunk region vertebra are free.Bones are pneumatic.

Pubic shafts with a plate-like, and slightly angled transverse cross-section.

Cerebral hemispheres elongate, slender and cerebellum is situated behind the midbrain and doesn't overlap it from behind or press down on it.

Neck attaches to skull from the rear as in dinosaurs not from below as in modern birds. Center of cervical vertebrae have simple concave articular facets.

Long bony tail with many free vertebrae up to tip (no pygostyle).

Premaxilla and maxilla bones bear teeth.Ribs slender, without joints or uncinate processes and do not articulate with the sternum.

Pelvic girdle and femur joint is archosaurian rather than avian (except for the backward pointing pubis as mentioned above).

The Sacrum (the vertebrae developed for the attachment of pelvic girdle) occupies 6 vertebra, where in modern birds the Sacrum covers between 11-13.

Metacarpals (hand) free (except 3rd metacarpal), wrist hand joint flexible.

Nasal opening far forward, separated from the eye by a large preorbital fenestra (hole).

Deltoid ridge of the humerus faces anteriorly as do the radial and ulnar condyles.

Claws on 3 unfused digits.

The fibula is equal in length to the tibia in the leg.

Metatarsals (foot bones) free.

Gastralia present.

--Now here are the 5 Avian features of Archaeopteryx:

Wings.

Feathers.

Opposable hallux (big toe).

Furcula (wishbone) formed of two clavicles fused together in the midline.

Pubis elongate and directed backward.

So, is Archaeopteryx a dinosaur, or a bird? In actuality it's both. Birds are the only extant clade of Dinosaurs today.

Ardi Fossil Description and Importance

One of the most hotly debated issues in current human origins research focuses on how the 4.4 million-year-old African species Ardipithecus ramidus is related to the human lineage. "Ardi" was an unusual primate. Though it possessed a tiny brain and a grasping big toe used for clambering in the trees, it had small, human-like canine teeth and an upper pelvis modified for bipedal walking on the ground... could further research reveal where Ardi lays in the ape family? Is it part of homo? Or is it an example of parallel evolution of other apes during the initial homo divergence?

Bacteria Stay Bacteria For A Reason

Considering the fact that "Bacteria" is an entire domain of life, why in the world would you expect a bacteria to magically change into an archaea or a eukaryote, like an animal or something... when we talk about evolution? Does this mean that an animal, in the animalia kingdom of the Eukarya domain of life has to entirely switch domains of life and become a bacteria, or Archaea before you will call it evolution? Life

Bacteria Uptaking Ancient DNA, Adding Novel Information

Oh look....more ways to add novel genetic information to a genome....which, apparently "doesn't happen, ever"....

From a bacterial perspective the environment is one big DNA waste yard. Researchers have now shown that bacteria can take up small as well as large pieces of old DNA from this scrapheap and include it in their own genome. This discovery may have major consequences – both in connection with resistance to antibiotics in hospitals and in our perception of the evolution of life itself.

Bacterial Communications For Synchronized Attack

Bacteria send each other chemical messengers to relay information about population density, and to help organize gene expression and actions into synchronicity, to enable a more powerful overall effect on their host or environment.

We are learning that this is how tiny little bacteria are able to team up to strike large animals such as ourselves effectively, and quickly.

A Bacterium, on it's own, wouldn't be able to do much at all to a human sized animal...yet bacteria can do so much damage to us.

As the bacterium reproduces, and the bacteria start to colonize, they send out chemical messengers to each other. This tells the bacteria that there is a pretty decent amount of bacteria present, which then means if they worked in sync, they could do some pretty good damage to their host, by sheer numbers. So they synchronize their virulence factor production and attack as a unit.

Imagine the antibiotic methods that could be produced if we were able to stop these chemical messages from being sent/received from/by bacteria? They wouldn't be able to synchronize, and their virulence factor production would be interrupted/altered/ceased....Amazing, isn't it?

Brainless Mold Making Dietary Choices

A species of nonneuronal slime mold, Physarum polycephalum, has the capabilities to conduct complex dietary distribution foraging. It essentially knows which food sources it needs, how much of it it needs and actually grows in proportion to these perceived needed-amounts.

It's making specialized dietary choices, yet lacks any sort of brain or neuronal cells.

Brainless Mold Solves Maze

A species of nonneuronal slime mold, Physarum polycephalum, has spatial memory capabilities and can actually solve mazes.

Chimpanzees

Chimpanzee Social Bonding Works Just Like Humans

The ability to form long-term cooperative relationships between unrelated individuals is one of the main reasons for human's extraordinary biological success, yet little is known about its evolution and mechanisms. The hormone oxytocin, however, plays a role in it.

Chimpanzees Use Meaningful Hand Gestures

A team of researchers has undertaken a study of chimpanzee hand gestures and their implementation in coordinated communication.

The team devised a task that demanded coordination among the chimps and a human to find a piece of food that had been hidden in a large outdoor area. The human experimenter did not know where the food was hidden, and the chimpanzees used gestures such as pointing to help the "team" get to the food.

Definition Of Primate

“Primates” are collectively defined as any gill-less, organic RNA/DNA protein-based, metabolic, metazoic, nucleic, diploid, bilaterally-symmetrical, endothermic, digestive, tryploblast, opisthokont, deuterostome coelemate with a spinal chord and 12 cranial nerves connecting to a limbic system in an enlarged cerebrial cortex with a reduced olfactory region inside a jawed-skull with specialized teeth including canines and premolars, forward-oriented fully-enclosed optical orbits, and a single temporal fenestra, -attached to a vertebrate hind-leg dominant tetrapoidal skeleton with a sacral pelvis, clavical, and wrist & ankle bones; and having lungs, tear ducts, body-wide hair follicles, lactal mammaries, opposable thumbs, and keratinized dermis with chitinous nails on all five digits on all four extremities, in addition to an embryonic development in amniotic fluid, leading to a placental birth and highly social lifestyle.

Differing Morphology in Homosexuals

There is a difference in hypothalamic structure between Heterosexual and Homosexual men, which may contribute to a better understanding of the neural basis of male sexual orientation.

There are also different neural circuits active during sexual arousal in homosexual and heterosexual men and this may contribute to a better understanding of the neural basis of male sexual orientation.

There are also differences in suprachiasmatic nucleus size between homosexual men and heterosexual men and this may contribute to a better understanding of the neural basis of male sexual orientation.

Domestic Cat Homologous Evidence for Common Descent

Domestic cats (Felis silvestris catus) sense of taste is extremely similar to that of other mammals with the exception of an inability to taste sweet stimuli.

This inability to taste sweet stimuli, lead to the hypothesis that the problem lies in the molecular receptors of the tongue. So genetic testing was conducted.

Geneticists identified the DNA sequences and examined the structures of the 2 known genes, Tas1r2 and Tas1r3, in cats, that encode the sweet taste receptor in other mammals, and then compared these with the sequence and structure of the same genes in dogs, humans, mice and rats, all species that respond to sweet stimuli.

The Tas1r3 gene in both cats and dogs are composed of 6 similarly sized exons and 5 introns. There was nothing within the cat Tas1r3 gene that would suggest that the cat gene was defective compared with that of the dog.

The Tas1r2 gene, however, contains a microdeletion of 247 base pairs in exon 3. This deletion is responsible for a frame shift that results in a premature stop codon at base pairs 57-59 of exon 4. By aligning cat Tas1r2 DNA sequences of exons 4, 5, and 6 with their dog counterparts, we found 4 additional stop codons: 1 in exon 4 due to a deletion at bp 123, and 3 in exon 6 due to a substitution at bp 95 and a deletion at bp 247. The multiple stop codons indicate that the cat Tas1r2 is a pseudogene.

After this discovery, they dug a little deeper...They confirmed the sequence of Tas1r2 in 6 additional unrelated healthy adult domestic cats, a tiger, and a cheetah. They found that the Tas1r2 gene in the tiger and the cheetah were also pseudogenes, and all the species had the identical 247-bp deletion in exon 3, had stop codons at the same positions in exon 4, and the second exon 6 stop codon.

The fact that these cats have the same two sweet-receptor genes as other mammals, yet one of them is riddled with identical mutations only found in cats, and not found in other mammals, shows direct evidence of homologous structures within families that are derived from a common ancestor, that are passed down via evolution. [Cats Lack a Sweet Taste Receptor]

Domestication of House Cats

The domestication of any animal is an interesting topic to discuss, as the origins of the domestication are very interesting to me. Who/what/when/why/and how did they decide to, and then implement, a plan to domesticate a certain breed/species of animal? And then how did this domestication spread around the world as seen in most domesticated animals?

Well just last week the earliest evidence for commensal processes taking part in the domestication of cats was found. Farming villages in need of a rodent-problem fix turned to cats for their solutions, it seems.

Examples of Modern Day Human Evolution

1. Adaptation to Higher Altitudes via mutations in Tibetan people
2. Mutations causing resistance to HIV in Modern Human day populations
3. Mutation causing increased bone density and strength

Farming and Cultivation Among Ants

Atta leaf cutter ants send out hordes of foragers to go and collect foliage from the surrounding area.

They bring these leaves back to the colony. But not to eat.

They use it to sustain their gardens. These ants grow and maintain gardens of Lepiotaceae fungus. They use the leaves as sustenance for the fungus to use to grow. They even provide anti-microbial to ward off pests and molds from ruining their food source.

Looks like ants beat us to farming and antibiotics a few million years ago.

Full Definition of Evolution

The most simplified, yet thoroughly explanatory/definition of evolution I can think of would be as follows: Evolution is...

VARIATION: 1) Variation exists in all populations. 2) Some of that variation is heritable. 3) Base pair sequences are encoded in a set of self-replicating molecules that form templates for making proteins, called DNA. 4) Combinations of genes that did not previously exist may arise via "shuffling" during replication, which alters the sequence of base pairs on a chromosome. 5) Copying errors (mutations) can also arise, because the self-replicating process is of imperfect (although high) fidelity; these mutations also increase the range of combinations of alleles (variations of genes) in a gene pool.

SELECTION: 6) Some of that heritable variation has an influence on the number of offspring able to reproduce in turn, including traits that affect mating opportunities, or survival prospects for either individuals or close relatives. 7) Characteristics which tend to increase the number of an organism's offspring that are able to reproduce in turn, tend to become more common over generations and propagate through a population; those that tend to decrease such prospects tend to become rarer. 8) "Sampling errors" (random chance) can occur in populations that alter the relative frequency of the various alleles for reasons other than survival/reproductive advantages, such as an avalanche randomly killing a select number of randomly distributed individuals that happened to be in the wrong place at the wrong time. 9) Migration of individuals from one population to another can lead to changes in the relative frequencies of alleles in the "recipient" population.

SPECIATION: 10) Populations of a single species that live in different environments are exposed to different conditions that can "favor" different traits. These environmental differences can cause two populations to accumulate divergent suites of characteristics. 11) A new species develops (often initiated by temporary environmental factors such as period of geographic isolation) when a sub-population acquires characteristics which promote or guarantee reproductive isolation from the alternate population, limiting the diffusion of variations thereafter.

SUFFICIENCY: 12) The combination of these effects tends to increase diversity of life forms; over the time frame from the late Hadean to the present, this becomes sufficient to explain the diversity of life observed on Earth, both in what is directly seen at present, and indirectly through geologic evidence from the fossil record.

Human Pseudogenized Vomeronasal System

The vomeronasal system is an important biological system in most animals. It is the system of pheromone detection, chemical messengers that carry information between individuals of the same species. The main organ of this system is the vomeronasal organ (VNO). The neurons in the VNO express receptors from 3 families, called V1R, V2R, and FPR. The protein-channel that this organ uses in mammals for it's nerve impulses, is the TRPC2 channel.

The VNO is semi-present in humans, it begins to develop, but regresses during human-fetal development. Humans also contain the TRPC2 gene, in pseudogeneized form, meaning it no longer codes for the impulse pathway. The human genome contains 120 V1R genes, and only 5 retain the ability to encode a functional receptor protein, and two of those 5 are only found to be functional in a proportion of the human population; they have been caught in the act of pseudogenisation. The human genome contains 20 V2R genes, none of which are functional.

Useful Links for Evolution

1. Amazing site chucked full of evolutionary evidence
2. List to creationist claims against evolution, and how they're wrong
3. (29+ Macroevolution evidences)
4. Peer reviewed scientific literature on Evolution
5. Peer reviewed scientific literature on Evolution
6. Daily scientific advancements, and evolution is always popping up almost everyday
7. Science updates
8. The national academies themselves on evolution
9. biological tree of life
10. interactive tree of life
11. more evidence for evolution

List of transitional forms

A transitional form is an organism that has features intermediate of its ancestors and progeny. The term is most common in evolution to refer to organisms that show certain features (wings, feathers, gills and so on) partly in development. In theory, every fossil is a transitional form if it has descendants and each living creature is a transition between its parent and its offspring. However, evolution is about the features of populations rather than individuals; the transition at the species level can be too small in fossils; so the list below concentrates on broad transitional features and the genus or larger group.

Invertebrate to Vertebrate

Unnamed Upper (U.) Pre-Cambrian chordate -- First to bear a primitive notochord; archaetypical chordate.

Pikaia gracilens-- Middle (M.) Cambrian chordate with lancelet-like morphology.

Haikouella-- Lower (L.) Cambrian chordate, first to bear a skull; archaetypical craniate.

Haikouichthys-- L. Cambrian quasi-vertebrate, intermediate in developing a vertebral column; archaetypical vertebrate.

Conodonts-- U. Cambrian to Triassic quasi-vertebrates with spinal cord; "bug-eyed lampreys".

Myllokunmingia-- L. Cambrian vertebrate with primitive spinal column; oldest true crown-group vertebrate.

Arandaspis-- L. Ordovician vertebrate, armoured jawless fish (ostracoderm), oldest known vertebrate with hard parts known from (mostly) complete fossils.

Jawless Fish to Jawed Vertebrate

Birkenia-- Silurian primitive, jawless fish, a typical member of the Anaspida.

Cephalaspis-- Silurian armoured jawless fish, archaetypical member of the "Osteostraca," sister group to all jawed vertebrates.

Shuyu-- Silurian to Devonian, armoured jawless fish belonging to Galeaspida, related to Osteostraca. Internal cranial anatomy very similar to the anatomy seen in basal jawed vertebrates. This similarity is directly implied with the translation of its name, "Dawn Fish," with the implication that it represents the "dawn of jawed vertebrates."

Acanthodian to Shark

Ptomacanthus-- sharklike fish, originally described as an acanthodian fish: brain anatomy demonstrates that it is an intermediate between acanthodians and sharks.

Cladoselache-- primitive/basal shark.

Tristychius-- another sharklike fish.

Ctenacanthus-- primitive/basal shark.

Paleospinax-- sharklike jaw, primitive teeth.

Spathobatis-- Ray-like fish.

Protospinax-- Ancestral to both sharks and skates.

Primitive jawed fish to bony fish

Acanthodians-- superficially similar to early bony fishes, and some have been identified as being the ancestors of sharks.

Palaeoniscoids-- primitive bony fishes.

Canobius, Aeduella-- palaeoniscoids with more advanced jaws.

Parasemionotus-- combination of modern cheeks with more primitive features, like lungs.

Oreochima-- first teleost fish.

Leptolepids-- vaguely herring-like ancestors of modern teleost fish. Lung modified into swim bladder.

Amphistium and Heteronectes-- percomorphs that demonstrate the transition of the eye location of flatfishes.

Fish to amphibian

Paleoniscoids-- both ancestral to modern fish and land vertebrates.

Osteolepis-- modified limb bones, amphibian like skull and teeth.

Kenichthys-- shows the position of exhaling nostrils moving from front to fish to throat in tetrapods in its halfway point, in the teeth.

Eusthenopteron, Sterropterygion-- fin bones similarly structured to amphibian feet, but no toes yet, and still fishlike bodily proportions.

Panderichthys, Elpistostege-- tetrapod-like bodily proportions.

Obruchevichthys-- fragmented skeleton with intermediate characteristics, possible first tetrapod.

Tiktaalik-- a fish with developing legs. Also appearance of ribs and neck.

Acanthostega gunnari-- famous intermediate fossil. most primitive fossil that is known to be a tetrapod.

Ichthyostega-- like Acanthostega, another fishlike amphibian.

Hynerpeton-- A little more advanced then Acanthostega and Ichtyostega.

Labyrinthodonts-- still many fishlike features, but tailfins have disappeared.

Lungfish--A fish-that has lungs.

Primitive to modern amphibians

Temnospondyls

Dendrerpeton acadianum

Archegosaurus decheni

Eryops megacephalus

Trematops

Amphibamus lyelli

Doleserpeton annectens

Triadobatrachus-- primitive frog

Vieraella

Karaurus-- primitive salamander

Amphibian to reptile

Proterogyrinus

Limnoscelis

Tseajaia

Solenodonsaurus

Hylonomus

Paleothyris

Early reptile to turtle

Captorhinus

Scutosaurus

Odontochelys Semitestacea-- partial formation of a turtle shell, showing how the hard underbelly, or plastron, formed first.

Deltavjatia vjatkensis

Proganochelys

Early reptile to diapsid (dinosaurs and modern reptiles except for turtle)

Hylonomus

Paleothyris

Petrolacosaurus

Araeoscelis

Apsisaurus

Claudiosaurus

Planocephalosaurus

Protorosaurus

Prolacerta

Proterosuchus

Hyperodapedon

Trilophosaurus

Reptile to mammal

Paleothyris

Protoclepsydrops haplous

Clepsydrops

Archaeothyris

Varanops

Haptodus

Dimetrodon

Sphenacodon

Biarmosuchia

Procynosuchus

Dvinia

Thrinaxodon

Cynognathus

Diademodon

Probelesodon

Probainognathus

Exaeretodon

Oligokyphus

Kayentatherium

Pachygenelus

Diarthrognathus

Adelobasileus cromptoni

Sinoconodon

Kuehneotherium

Eozostrodon

Morganucodon-- a transition between "mammal-like reptiles" and "true mammals".

Haldanodon

Peramus

Endotherium

Kielantherium

Aegialodon

Steropodon galmani

Vincelestes neuquenianus

Pariadens kirklandi

Kennalestes

Asioryctes

Cimolestes

Procerberus

Gypsonictops

Dinosaur to bird

Allosaurus--A large therapod with a wishbone

Coelophysis

Compsognathus--A small coeleosaur with a wishbone

Eoraptor

Epidendrosaurus

Herrerasaurus

Ceratosaurus

Compsognathus

Sinosauropteryx

Protarchaeopteryx

Caudipteryx

Velociraptor

Deinonychus

Oviraptor

Sinovenator

Beipiaosaurus

Lisboasaurus

Sinornithosaurus

Microraptor-- a feathered bird with distinctly dinosaurian characteristics, such as its tail.

Xiaotingia-- slightly earlier than Archaeopteryx, slightly more like a dinosaur and less like a bird

Archaeopteryx-- the famous bird-with-teeth.

Rahonavis

Confuciusornis

Sinornis

Patagopteryx

Ambiortus

Hesperornis

Apsaravis

Ichthyornis

Columba-- One of many typical modern birds

Primates

Darwinius masillae-- a link between earlier primates and later ones.

Non-human primate to human

Sahelanthropus tchadensis-- One of the oldest known species in the human family tree. Lived around 6.5-7 million years ago, one of the earliest bi-pedal fossils.

Orrorin tugenensis-- Over 20 fossils of the 6 million year old species have been found and show very human-like morphology.

Ardipithecus ramidus-- 4.5 million year old species showing bi-pedal adaptations and opposable thumbs.

Australopithecus-- a genus of bipedal apes

Australopithecus anamensis

Australopithecus afarensis

Kenyanthropus platyops-- 3.5 million year old himinim fossil, most likely a subspecies of Australopithecus

Australopithecus africanus

Australopithecus garhi

Australopithecus sediba-- advanced australopithecus showing more human features

Australopithecus aethiopicus

Australopithecus robustus

Australopithecus boisei

Homo habilis-- a transitional form from Australopithecus to later Homo

Homo rudolfensis-- a type of Homo habilis or a different species

Homo ergaster-- a form of Homo erectus or a distinct species

Homo georgicus-- a form of Homo Erectus or a distinct species

Homo erectus-- a transitional form from Australopithecus to later Homo (Latin for humans) species

Homo antecessor-- is an extinct human species, or subspecies, dating from 1.2 million to 800,000 years ago

Homo heidelbergensis-- A possible common ancestor of modern man and homo neanderthalensis

Homo neanderthalensis-- They may or may not have done Humpy bumpy with modern humans.

Homo floresiensis-- Extinct Homo species, living 94,000-12,000 years ago, used tools, bipedal, very human-like

Cro-magnon-- considered early modern human and perhaps as smart as we are

Cetaceans

Indohyus-- a vaguely chevrotain-like or raccoon-like aquatic artiodactyl ungulate with an inner ear identical to that of whales.

Ambulocetus-- an early whale that looks like a mammalian version of a crocodile

Pakicetus-- an early, semi-aquatic whale, a superficially wolf-like animal believed to be a direct ancestor of modern whales.

Rhodocetus-- An early whale with comparatively large hindlegs: not only represents a transition between semi-aquatic whales, like Ambulocetus, and obligately aquatic whales, like Basilosaurus.

Basilosaurus-- A large, elongated whale with vestigial hind flippers: transition from early marine whales (likeRhodocetus) to modern whales

Dorudon-- A small whale with vestigial hind flippers, close relative of Basilosaurus.

Lizards Gaining New Digestive Structures Via Evolution

A very strong piece of evidence for evolution is that we actually see creatures evolving within human lifetimes. Th isolation of a group of lizards from the original population leaded to changes in head and jaw size, digestive structure along social habits.

Apr. 18, 2008— In 1971, biologists moved five adult pairs of Italian wall lizards from their home island of Pod Kopiste, in the South Adriatic Sea, to the neighboring island of Pod Mrcaru. Now, an international team of researchers has shown that introducing these small, green-backed lizards, Podarcis sicula, to a new environment caused them to undergo rapid and large-scale evolutionary changes.

Striking differences in head size and shape, increased bite strength and the development of ENTIRELY new structures in the lizard‘s digestive tracts were noted after only 36 years, which is an extremely short time scale, says Duncan Irschick, a professor of biology at the University of Massachusetts Amherst. These physical changes have occurred side-by-side with dramatic changes in population density and social structure.

Observed changes in head morphology were caused by adaptation to a different food source. According to Irschick, lizards on the barren island of Pod Kopiste were well-suited to catching mobile prey, feasting mainly on insects. Life on Pod Mrcaru, where they had never lived before, offered them an abundant supply of plant foods, including the leaves and stems from native shrubs. Analysis of the stomach contents of lizards on Pod Mrcaru showed that their diet included up to two-thirds plants, depending on the season, a large increase over the population of Pod Kopiste.

As a result, individuals on Pod Mrcaru have heads that are longer, wider and taller than those on Pod Kopiste, which translates into a big increase in bite force, says Irschick. Because plants are tough and fibrous, high bite forces allow the lizards to crop smaller pieces from plants, which can help them break down the indigestible cell walls. Examination of the lizard‘s digestive tracts revealed something even more surprising. Eating more plants caused the development of new structures called cecal valves, designed to slow the passage of food by creating fermentation chambers in the gut, where microbes can break down the difficult to digest portion of plants. Cecal valves, which were found in hatchlings, juveniles and adults on Pod Mrcaru, have never been reported for this species, including the source population on Pod Kopiste.

Mutations Increasing Lifespan of Organisms

New research in simple animals suggests that combining mutants can lead to radical lifespan extension. Scientists at the Buck Institute combined mutations in two pathways well-known for lifespan extension and report a synergistic five-fold extension of longevity in the nematode C. elegans.

Oldest Tarsiiforme Fossil and Its Evolutionary Implications

So, more evidence comes to light to affirm previous claims that our simiiforme lineage diverged from tarsiiformes around 60 million years ago.

The most basal tarsiiforme taxon has been dated to around 55 million years ago, making an initial tarsiiforme/simiiforme divergence occurring around 60 million years ago a very likely possibility.

This also supports the claims that us haplorhines started out as very small little cute bundles of hair.

Paravian Fossil Affirms Avian Origins

More and more reasons to accept the claim that birds are a specialized and evolved subset of avian, theropod dinosaurs.

A Jurassic avialan dinosaur from China has resolved the early phylogenetic history of birds, affirming previous predictions and assumptions about the emergence of birds from theropod dinosaurs.

Interesting, so creationists definitely can't say that Archaeopteryx was a paravian and not an avialan (the typical it's a reptile not a bird retort), and we can confidently say birds made their way into the world during the later end of the Jurassic period (145-165 mya).

Predation Facilitates Evolution

Although theory indicates that natural selection can facilitate speciation as a by-product, demonstrating ongoing speciation via this by-product mechanism in nature has proven difficult. Morphological, molecular, and behavioral data are examined here to investigate ecology‘s role in incipient speciation for a post-Pleistocene radiation of Bahamas mosquitofish (Gambusia hubbsi) inhabiting inland blue holes (water-filled, vertical caves). It is shown that adaptation to divergent predator regimes is driving ecological speciation as a by-product. Divergence in body shape, coupled with assortative mating for body shape, produces reproductive isolation that is twice as strong between populations inhabiting different predator regimes than between populations that independently evolved in similar ecological environments. These results suggest ongoing ecological speciation among blue holes, resulting as a by-product of divergence in ecologically important traits.

Especially strong confirmation of the hypothesis of ecological speciation via the by-product mechanism is provided when each of three kinds of evidence is available: divergent natural selection between environments, replicated trait evolution in independent populations, and greater reproductive isolation between ecologically divergent pairs of populations than ecologically similar ones resulting as a by-product of divergent traits. In this study, morphological data were used to test for divergent natural selection, molecular data to test for evolutionary independence among populations exhibiting similar phenotypes, and mate-choice trials were conducted to test for ecologically-associated premating isolation.

Primate Macroevolution Overlook

Here is a layout of primate macroevolutionary history. There are 2 main pieces of the picture.

A Chronogram showing posterior divergence ages for the 21 Hominoidea species. The study agrees with, and corroborates already existing phylogenetic trees of great ape evolution, but this chronogram adds in divergence times as well. (Homd = Hominoidea, Hom = Hominidae, Hyl = Hylobatidae). The circles at the various divergence nodes represent the maximum likelihood bootstrap support (circles: black 100–95%, gray 95–70%, white 70–50%; white squares: 50–0%).

Along with the chronogram to the left, on the right is the molecular marker sampling that shows the genes used to calculate divergence times (with a Bayesian relaxed molecular clock method and four fossil calibrations) along with the biogeographic distribution label for each taxa (the biogeographical labels are the 2 letters on the left of the table: either AF = Africa or AS = Asia.) The names of the genes are given above the table. The genes sampled for the dataset are marked in black squares, while unused genes are symbolized by white squares. Genetics don't lie...

History

Examples of Documented Speciation Events

Just a very short list of observed Speciation events.

1. An excellent example of evolution in action is a 14-year experiment done with Anolis lizards.(Losos et al, 1997) A single species of Anolis lizards was spread across 14 Caribbean islands none of which had any previous lizard populations. Over the time of the experiment, the lizards each adapted to their respective environments. Several new species of lizards evolved. The lizards each changed body shape in response to the flora in their environment. In fact, scientists were able to predict exactly how each lizard population would evolve before seeing the results. Scientists estimate that this change was on the order of 200 darwins, which are measured units of evolutionary change. In comparison, the average rate observed in the fossil record is only 0.6 darwins.(Gingerich, 1983)
2. Irish monks originally brought the house mouse to the Faeroe Islands, where it has quickly diverged in different species, or possibly sub-species, in less than 250 years. (Stanley,1979)
3. Less than 5,000 years ago, a sandbar formed and cut off Lake Nagubago from the larger Lake Victoria. Since then, at least 5 new species of cichlid fish have evolved in Lake Nagubago, and these species are found nowhere else in the entire world.(Mayr, 1970)
4. Gulls of the genus Larus form an evolutionary ring around the North Pole, which acts as a geographic barrier for their population. Although some have argued that this is technically not an example of a ring species(Liebers et al., 2004), it is certainly an example of speciation in action.
5. The early geneticist Hugo de Vries observed an act of speciation while studying the evening primrose plant. The original species, Oenothera lamarckiana, had 14 chromosomes, while the new species had 28. The new species was unable to breed with Oenothera lamarckiana, and thus he named it Oenothera gigas.(De Vires, 1905)
6. When a predator was introduced to the environment of the unicellular Chlorella algae in a lab test, scientists observed the algae cells bond together in colonies, and eventually became an entirely new multicellular species. One could even argue that this change extends past the species level. FC is the unicellular chlorella algae, Oc is the predator introduced to the environment, and CC is the new multicellular algae. This is not simply a "cell colony", but a new multicellular organism. The multicellularity was achieved by a mutation that fused the cell wall of the mother cell and its daughter cell together. Because these cells are thus dependent upon each other for survival, the new organism is multicellular and not a simple bacterial colony.(Boraas et al., 1998)
7. The new species of mosquito Culex pipiens molestus recently formed in, and is endemic to, the London Underground rapid transit system. It most likely speciated from the surface population Culex pipiens, although it is now genetically dissimilar enough to be considered another. (Byrne et al., 1999)
8. The finch populations of the Galapagos islands have been famous ever since they were included as elegant examples of natural selection in Darwin's On the Origin of Species. In recent times, scientists have successfully observed a new species of finch develop after an extreme bottleneck in the finch population on the island Daphne Major, caused by a drought. This new species refuses to mate with its sister-species, and thus is reproductively isolated. Over time, it will genetically diverge; this is evolution in action just as Darwin predicted, in the very place where the formation of his ideas have their roots(Peter Grant and Rosemary Grant 2009)

To add to this...here are several more cases you can research up on...both animals and plants. Kew Primrose (Primula kewensis), Tragopogon, Raphanobrassica, Hemp Nettle (Galeopsis tetrahit), Madia citrigracilis, Brassica, Maidenhair Fern (Adiantum pedatum), Woodsia Fern (Woodsia abbeae), Stephanomeira malheurensis, Maize (Zea mays), Yellow Monkey Flower (Mimulus guttatus), Drosophila paulistorum, Drosophila melanogaster, Houseflies, Apple Maggot Fly (Rhagoletis pomonella), Gall Former Fly (Eurosta solidaginis), Flour Beetles (Tribolium castaneum), Nereis acuminata, Drosophila paulistorum, Cichlid fishes

Refutation of The Metamorphosis Argument Against Evolution

Creationists, every now and again, try to use holometabolous and hemimetabolous insects (minus the actual scientific terminology, of course) as a way to attempt (futilely) to "poke holes" in evolution....even though that literally presents no evidence for their own case....

Little do they know, that holometabolous and hemimetabolous insect's Pronymphal development and subsequent ecdyses, are directed, affected, and controlled, by the prothoracicotropic hormone (PTTH) inducing Ecdysone release from the prothoracic glands, and neotenin's "juvenile-based equilibrium" control via distribution in the insect's haemolymph.

Experiments using the aforementioned Endocrinology-based facts, show that holometabolous and hemimetabolous insects can skip the usual multiple developmental-ecdyses and go straight to a diminutive adult form after just one. Showing a definite tie between slight changes in hormonal balances, and entirely new developmental process.

Also; the bHLH-PAS protein, MET, or the "zinc-finger", Kr-h1, can be altered to achieve precocious metamorphosis in insects...Further showcasing the DRASTIC, yet easily accomplished, manipulation of insect development by simple changes in hormonal and protein levels.

Also; studies on the broad range (Br) protein in insect development show that:

1. Ametabolous insects only show this protein during embryonic development. 2)Hemimetobolous insects show it slightly during embryonic development, and more during nymphal stages.
2. Holometabolous insects only show it during metamorphic stages, and none during embryonic development.
3. That this protein is a pupal determinant.
4. That neotenin suppresses the activation of Br.
5. That Br production is non-existent in holometabolous insect's embryonic development, due to an earlier onset of neotenin activation.
6. That neotenin's heavy, earlier appearance in holometabolous insect's will subsequently delay the Br protein until neotenin tetirs decline at the penultimate instar, onsetting a massive influx of Br, which we call a complete metamorphosis.
7. That neotenin's light, earlier appearance in hemimetabolous insect's will subsequently suppress Br's activation slightly during embryogenesis, but not completely, and cause a minor influx of Br later on in development when neotenin tetirs decline, which we call an incomplete metamorphosis.
8. That this neotenin/Br relationship is/was a major driving force in metamorphic evolution.

Further showcasing the drastic, yet easily accomplished, manipulation of insect development by simple changes in protein levels.

Considering the fact that the earliest insects were ametabolous, exclusively, we can more easily understand the changes necessary for holometabolous and hemimetabolous insects to arise. We can also corroborate the aforementioned molecular and phylogenetic/embryonic evidence with the observable gradient of change from ametabolous insects, to metamorphic insects, both hemimetabolous and holometabolous.

Refutation of the Irreducible Complexity of The Flaggelum

Another criticism of evolutionary theory is that the bacterial flagellum could not have possibly evolved via natural processes. Although this one tiny piece of mystery would never debunk an entire scientific theory in one swoop, it's worth noting anyways.

Critics claim that the flagellum would only work if it was made fully formed, all at once, and that there is no possible evolutionary pathway that it could have came about, and so therefore, there must have been a special creation event via an intelligent designer and they deem this "irreducible complexity".

This is simply false and relies on ignorance and projection of that ignorance as if it's fact.

The flagella has been altered/reduced and remains functional.

A subset of parts of the flagella conferring function.

Multiple mutations conferring a single function in flagella.

Bacterial flagella at first sight appear uniquely sophisticated in structure, so much so that they have even been considered 'irreducibly complex' by the intelligent design movement. However, a more detailed analysis reveals that these remarkable pieces of molecular machinery are the product of processes that are fully compatible with Darwinian evolution. In this chapter we present evidence for such processes, based on a review of experimental studies, molecular phylogeny and microbial genomics. Several processes have played important roles in flagellar evolution: self-assembly of simple repeating subunits, gene duplication with subsequent divergence, recruitment of elements from other systems ('molecular bricolage'), and recombination. We also discuss additional tentative new assignments of homology (FliG with MgtE, FliO with YscJ). In conclusion, rather than providing evidence of intelligent design, flagellar and non-flagellar Type III secretion systems instead provide excellent case studies in the evolution of complex systems from simpler components.

As you can see, Irreducible Complexity is merely an argument from ignorance and is no mystery to real scientists.

Atavism

Rudimentary Chicken Penis Development

Just so everyone knows, chickens have the genetics for making a penis still, but the growth of the penis stops after day 9, due to Bmp4 proteins halting the development.

So...why do chickens have the genetics for growing a penis, if they no longer fully utilize these genetics after day 8-9 of development?

Faulty design? Coincidence crafted by the devil? or predicted evolutionary adaptations?

Atavistic Human Tails Necessitate Evolution

Embryonic research has resulted in an amazing discovery of evolutionary links found in embryonic humans, we grow a tail while in the womb but absorb it into what is now a coccyx. (Fallon and Simandl 1978; Moore and Persaud 1998, pp. 91-100; Nievelstein et al. 1993). Although, sometimes this abrupt half of tail growth doesn't happen. Resulting in the growth of a human tail. The true human tail (as opposed to skeletal anomolies) is characterized by a complex arrangement of adipose and connective tissue, central bundles of longitudinally arranged striated muscle in the core, blood vessels, nerve fibres, nerve ganglion cells, and specialized pressure sensing nerve organs (Vater-Pacini corpuscles), enlarged coccygeal vertebrate, extra non-coccygeal vertrbrate, muscles, nerve ganglion and slight voluntary movement. It is covered by normal skin, replete with hair follicles, sweat glands, and sebaceous glands. (Dao and Netsky 1984; Dubrowet al. 1988; Spiegelmann et al. 1985).

In fact, the genes that control the development of tails in mice and other vertebrates have been identified (the Wnt-3a and Cdx1 genes; Greco et al. 1996; Prinos et al. 2001; Schubert et al. 2001; Shum et al. 1999; Takada et al. 1994). As predicted by common descent from the atavistic evidence, these tail genes have also been discovered in the human genome (Katoh 2002; Roelink et al. 1993).

We have the same genes that mice and other vertebrate use to grow a tail.

Whales and Teeth Genes in Whales

Using the idea that all mammals, including whales, descend from a common ancestor via evolutionary common descent, many amazing predictions can be made. One of these being the predictive hypothesis that mammals that no longer have teeth or have enameless teeth, descended from earlier mammals that did have teeth or enamel-capped teeth, so these modern toothless and enamelless mammals should have copies of the gene that codes for the enamelin protein, but that the enamelin gene in these species would contain mutations that render it a nonfunctional pseudogene. Unsurprisingly, all the genetics match perfectly with what evolution predicted.

Vestigiality Of Hiccups Uncovered

Signals are sent from the human brain, through the phrenic nerves, that induce synchronous spasms of the diaphragm. The subsequent sharp inhalation of air closes the epiglottis. This is commonly known as the hiccups. The evidence, as laid out by Dr. Straus (2003), that it is a vestigial reflex is as follows:

1. Amphibians have homologues motor pathways that cause similar inhalation (of water into their gills) and closing of the epiglottis (to prevent aspirating water into their lungs).
2. Motor pathways necessary for hiccupping complete embryological development before those of lung functionality do.
3. Both hiccups and amphibian water gulping are inhibited by the detection of high CO2 blood concentration by chemoreceptors.
4. Both hiccups and amphibian water gulping are outright stopped by the binding of (RS)-4-amino-3-(4-chlorophenyl) butanoic acid (Baclofen) to gamma-aminobutyric acid B receptors.