---------------- #1505 - Molly’s Grandpa was a Llama?
- Molly is a Golden Retriever, 7 months old and 50 pounds. My brother, Bob, wanted to know her pedigree. She came from a flea and burr infested farm in Napa at 3 months and was considered a rescue dog. Her lineage goes back to Scotland where her ancestors were bred for retrieving water fowl and game birds. In the 18th century guns were getting better and the downed game was too hard to find. Golden Retrievers were ideal for the job. Her lineage goes back to over 120 million years. Then, they were called Llamas.
-
- Science now knows that mammals and dinosaurs lived together for millions of years. 65,000,000 years ago dinosaurs died out and mammals took over and began to diversify. Mammals began as small, shrew-like creatures, some up to the medium sized dog. From there, evolution created a diversity of mammals where today we have 4,316 different species of mammals.
-
- Mammals are different from other creatures in that they have fur, or hair, are warm-blooded, and produce milk. They have live births, with a few mammals that lay eggs ( platypus), and a few that have a mother’s pouch (kangaroos), but 90% are placental mammals.
-
- Of these placental mammals there are at least 23 categories, called orders, and within these orders there are 4,316 different species. Each has a Latin name but I will just use a few representatives with common names for each species. For example the largest number of species is in the order “Rodentia” which has 1,995 species of mice, squirrels and guinea pigs. Here is a table of the order and species:
-
---------- 1 ------------ mice, squirrels ---------- 1,995 species
---------- 2 ----------- rabbits ------------------------ 80
---------- 3 ------------ bats -------------------------- 925
---------- 4 ----------- bears, cats, dogs, seals ---- 280
---------- 5 ----------- monkeys, men -------------- 233
---------- 6 ----------- whales, dolphins ------------- 78
---------- 7 ------------ cows, pigs, deer ------------ 215
---------- 8 ------------ horses, rhinos ------------- -- 18
---------- 9 ------------ sloth’s, anteaters ------------ 29
---------- 10 ----------- pangolins (1) ----------------- 7
---------- 11------------ flying lemurs ---------------- 2
---------- 12------------ aardvarks (5) ----------------- 1
---------- 13------------ manatees ---------------------- 4
---------- 14------------ hyraxes (2) ------------------- 11
---------- 15------------ elephants ---------------------- 2
---------- 16------------ elephant shrews ------------- 19
---------- 17------------ hedgehogs ------------------- 21
---------- 18------------ moles ------------------------- 42
---------- 19------------ tree shrews ------------------ 19
---------- 20------------ shrews ---------------------- 312
---------- 21------------ tenrecs, moles (footnote 3) - 24
---------- 22------------ golden moles ---------------- 18
---------- 23------------ solenodons (footnote 4) ----- 2
-
- We can try to combine these orders into groups that have common characteristics in order to determine a common ancestor. Common characteristics might be similar teeth, similar toes or hooves, similar spines, etc. Another way to combine these species into a family tree is to group those with the most similar DNA. This review does not go into the details of mutations in DNA. But, evolution has occurred through mutations in the DNA code. The mutations that improve the species, or create another species that are better survivors, live on. Those with the poor mutations die off. Only the strong survive.
-
- The DNA string is unique to each species as it is passed on to generation after generation. When you get back to common ancestors of species they have common DNA mutations. So, without going into the explanations here are the results:
-
The genetic differences in DNA between:
-
---------------- humans -------------- chimpanzes ------------ 1.24%
---------------- humans -------------- gorillas ---------------- 1.62%
---------------- humans -------------- orangutans -------------- 3.08%
-
----------------- chimps ----------------gorillas ---------------- 1.63%
----------------- chimps -------------- orangutans -------------- 3.13%
-
----------------- gorillas ------------ orangutans --------------- 3.09%
-
- Using DNA results, humans are more like chimps than any other species. And, humans are to gorillas almost as chimps are to gorillas. Using this data from the DNA we conclude that humans and chimps had a common ancestor from which both species diverged 6,500,000 years ago. And, humans and chimps diverged from gorillas some 7,500,000 years ago. These species of humans, chimps and gorillas diverged from orangutans with a common ancestor 16,000,000 years ago.
-
- It is important to note that only males were included in this DNA survey, ha, ha.
-
- We are interested in Molly’s common ancestors. Together dogs and bears are in the species “ Carnivores”. The number of nucleotide differences between dogs, bears, llamas, and antelope are:
-
-------------------- dogs --------------- bears ------------- 36 different nucleotides
------------------- dogs --------------- llamas ------------ 35
-------------------- dogs --------------- antelope ---------- 46
-
-------------------- bears -------------- llamas ------------ 45
-------------------- bears -------------- antelope ---------- 50
-
- It looks like dogs are more closely related to llamas than to bears. But, comparing dogs and bears to llamas they are 10 differences apart. Comparing them to antelope they are only 5 differences apart. Dogs and bears had a common ancestor with llama and antelope some 80,000,000 years ago.
-
- As best we can determine there evolved two basic groups of mammals. One from Africa and one from the Northern Latitudes.
-
From Africa common ancestors existed:
-
65,000,000 years ago for:
------------elephants
----------- hyraxes (footnote 2)
----------- manatees
-
and 80,000,000 years ago for:
---------- aardvarks (footnote 5)
---------- elephant shrews
---------- tenrecs (footnote 3)
-
- As best we can determine from Northern Latitudes common ancestors existed:
-
80,000,000 years ago for:
------------rabbits
---------- mice
---------- tree shrews
------------flying lemurs
---------- primates, you and me Leroy
-
and 90,000,000 years ago for:
---------- hedgehogs
---------- bats
--------- dogs and bears
---------- pangolins (footnote 1)
----------- horses
----------- pigs, whales
-
- This grouping certainly had something to do with continental drift when Africa separated from Gondwana some 120,000,000 years ago. South America separated from Africa some 105,000,000 years ago. South America joined up with North America some 90,000,000 years ago. The categories for these mammals come together with a common mammal ancestor some 110,000,000 years ago when they were all shrews. Then, the dinosaurs died off some 65,000,000 years ago. Interesting!
-----------------------------------------------------------
-
(1) Pangolons are a scaly anteater. They look like a walking pine cone that is up to 3 foot long. They can curl up into an armored ball with razor sharp scales for protection. Its claws are also sharp for climbing and burrowing.
-
(2) Hyrax is a small rabbit-like mammal said to be the closest living relative to the elephant. Found in Africa and the Middle East it has fossil records dating back 40,000,000 years ago.
-
(3) Tenrecs are found in Madagascar and Africa. They vary in size from shrew-like to opossum-like. They are omnivorous and nocturnal and usually live in groups.
-
(4) Solenodons are shrew-like mammals that resemble a species very closely to those living with the dinosaurs. They have long snouts and eat insects. Their tits are on their butts and their saliva is venomous. Once adult they are solitary animals.
-
(5) Aardvarks are called the ant-bear because it is the size of a pig. It is a living fossil. It is nocturnal and feeds on ants and termites. It has a long, sticky tongue. It borrows out a home. Its predators are lions and leopards and for defense it will lie on its back and slash with its long claws.
-
- From review #873 written January 15, 2008.-
--------------------------------------------------------------------------------------------------
RSVP, please reply with a number to rate this review: #1- learned something new. #2 - Didn’t read it. #3- very interesting. #4- Send another review #___ from the index. #5- Keep em coming. #6- I forwarded copies to some friends. #7- Don‘t send me these anymore! #8- I am forwarding you some questions? Index is available with email and with requested reviews at http://jdetrick.blogspot.com Please send feedback, corrections, or recommended improvements to: jamesdetrick@comcast.net.
or, use: “Jim Detrick” www.facebook.com, or , www.twitter.com.
707-536-3272, Monday, October 29, 2012
No comments:
Post a Comment