By: David Quesada
Chordata
Introduction to Chordata
This phylum includes birds, fish, mammals, amphibians, and reptiles. Seventy-five thousand species belong to this phylum including the likes of humans and the worlds fastest and largest animals: the peregrine falcons and blue whales. Animals in this phylum share the characteristics of being bilaterally symmetric as well as having a segmented vertebrae. The notochord characteristic give us the name "chordata," latin for "string" or "rope."
This phylum includes birds, fish, mammals, amphibians, and reptiles. Seventy-five thousand species belong to this phylum including the likes of humans and the worlds fastest and largest animals: the peregrine falcons and blue whales. Animals in this phylum share the characteristics of being bilaterally symmetric as well as having a segmented vertebrae. The notochord characteristic give us the name "chordata," latin for "string" or "rope."
Blue Whale (Balaenoptera Musculus)
Blue whales are diocious and sexually reproduce. From ages five to ten blue whales reach sexual maturity. They are dioecious and sexually reproduce. Sexual reproduction begins when blue whales migrate to the equator during the winter months as food begins to become scarce. Once near the equator, whales use echolocation and sonar to find mates. These sounds can be heard underwater for miles. Once the male and female meet, a unique ritual takes place. These rituals include rolling around each other, diving together, and, finally, having sex. The male thrusts his penis inside the female's vagina and ejaculates. The reproductive system of a blue whale is similar to the human in many respects. The males have penises and testicles (they do not have a penile bone) while the female whales have vaginas with ovaries. Once an egg is fertilized (Internal fertilization), it is held in the uterus of the female for 10-12 months. Whales give birth to live offspring, which they then take care of for the next year until it reaches adulthood.
More info at:
http://www.whalefacts.org/how-do-whales-reproduce/
http://education-portal.com/academy/lesson/male-reproductive-system-external-anatomy.html#lesson
More info at:
http://www.whalefacts.org/how-do-whales-reproduce/
http://education-portal.com/academy/lesson/male-reproductive-system-external-anatomy.html#lesson
Peregrine Falcon (Falco Peregrinus)
Unlike mammals, birds, including the falcon, have a cloaca which serves as the birds cavity for the urinary, digestive, and reproductive systems. During the spring mating season the cloaca swells which causes it to protrude from its body. A similar process occurs within the ovaries and testes, they swell and begin producing sperm and eggs. The falcon carries the sperm in his cloaca until a mating opportunity arrises. Only then does he eject it into the female where she then carries it until it fertilizes an egg. An egg then develops within the bird which is then laid in a nest anywhere from a couple of days to a couple of weeks. The falcon watches over them and protects them until the offspring hatches and are able to live independently. It is important to recognize birds have internal fertilization and are dioecious unlike other phylums covered in this website.
Find more at:
http://www.birdsnways.com/wisdom/ww33eiv.htm
http://www.birdsnways.com/wisdom/ww32eiv.htm
Find more at:
http://www.birdsnways.com/wisdom/ww33eiv.htm
http://www.birdsnways.com/wisdom/ww32eiv.htm
American Alligator (Alligator Mississippiensis)
When alligators are 7 to 12 years old they begin to sexually reproduce. Alligators reproduce internally and are dioecious. They mate in a marshy, hot, and humid climate when food is abundant in the spring and summer seasons. At night in shallow waters females attract alligators by making noises and ripples in the water. To test the strength of each other they will often push or shove each other. After courting for weeks the couple mates have sex. In this process the male injects his sperm from his gonads into the female cloaca. The reproductive system of the alligator resembles that of the bird suggesting that they have a common ancestor. Then an egg begins to develop which is laid by the female within the next couple of weeks. The sex of the offspring is then determined by the temperature of the nest. Males are formed by a nest temperature of 93 degrees and above while females are produced by nest temperatures of eighty six and below. The hatching ratio is five females to one male.
More info:
http://www.arca.museus.ul.pt/ArcaSite/obj/gaia/MNHNL-0000797-MG-DOC-web.PDF
http://channel.nationalgeographic.com/wild/worlds-weirdest/videos/female-man-parts/
More info:
http://www.arca.museus.ul.pt/ArcaSite/obj/gaia/MNHNL-0000797-MG-DOC-web.PDF
http://channel.nationalgeographic.com/wild/worlds-weirdest/videos/female-man-parts/