Go Back   Wild About Britain > British Wildlife > Mammal Forums

» November 2009

S M T W T F S
1 2 3 4 5 6 7
8 9 10 11 12 13 14
15 16 17 18 19 20 21
22 23 24 25 26 27 28
29 30 12345

» Stats

Members: 32,223
Threads: 48,348
Posts: 524,132
Top Poster: glsammy (13,193)
Welcome to our newest member, edward v
Welcome to the Wild About Britain forums
Reply

 

LinkBack Thread Tools Display Modes
  #1 (permalink)  
Old 03-07-2009, 11:37 PM
KeenTeen17's Avatar
Commander of the Wild Empire
 
Join Date: Aug 2008
Location: Preston in NW
Posts: 3,626
Red and Grey Hybridisation

I recently got into a debate with the family about why do Greys and Red Squirrels not hybridise. I told them that they don't because due to the fact that the Grey is American and the Red is English native. Is this right or have there been recorded hybrids between the 2?
__________________
Lancashire Nature

Last edited by KeenTeen17; 03-07-2009 at 11:52 PM.
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote
  #2 (permalink)  
Old 03-07-2009, 11:51 PM
Commander of the Wild Empire
 
Join Date: Mar 2007
Posts: 1,549
Re: Red and Grey Hybridisation

Well, they are in the same genus (Sciurus), but nobody has described a hybrid as far as I know. Perhaps the size difference is a problem.

henrya
__________________
Sometimes ice cream just has to take priority over everything.
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote
  #3 (permalink)  
Old 04-07-2009, 06:33 AM
Knight Commander of the Wild Empire
 
Join Date: Jul 2006
Posts: 7,437
Re: Red and Grey Hybridisation

I'm not aware of any hybrids, but the fact that one is American + the other European alone doesn't make hybridisation impossible; think of all the american Canada x European Greylag hybrids or problems with Ruddy x white-headed Ducks.

However geographical isolation is an evolutionary factor that leads to speciation.
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote
  #4 (permalink)  
Old 04-07-2009, 01:06 PM
mbaldw's Avatar
Wild Member
 
Join Date: Jan 2006
Location: Southampton
Posts: 158
Re: Red and Grey Hybridisation

Quote:
I recently got into a debate with the family about why do Greys and Red Squirrels not hybridise.
I've never come across any records of hybrids between these two species, although -- as aeshna5 said -- the fact that one's American and the other is European in origin doesn't preclude hybridization. They certainly have the same number of chromosomes (2n = 40) and, although this is not the only necessary requisite, this does suggest that any hybrids could be fertile. Personally, I'm inclined to think that the reason they don't interbreed is probably related to the observation that the two species generally do not occur sympatrically (i.e. their ranges tend not to overlap, producing a form of geographical isolation). So, the opportunity to interbreed probably doesn't raise itself very often, if at all. Of course, even if their ranges did overlap, merely being in the the same place at the same time doesn't mean that you'd necessarily expect hybridization.

Cheers,
Marc.
__________________
Marc Baldwin
My Website - Wildlife Online
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote
  #5 (permalink)  
Old 04-07-2009, 02:35 PM
Gaina's Avatar
Commander of the Wild Empire
 
Join Date: Jun 2006
Location: Somerset, UK
Posts: 1,338
Blog Entries: 2
Re: Red and Grey Hybridisation

If red and grey ranges don't overlap, I'd be interested to know how the grey passes the parapoxy virus on to the reds.

I've just been reading a bit about the virus and it also occurs in sheep, goats cattle and New Zealand Red Deer.
__________________
Least favourite animal: Humans.
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote
  #6 (permalink)  
Old 04-07-2009, 05:11 PM
mbaldw's Avatar
Wild Member
 
Join Date: Jan 2006
Location: Southampton
Posts: 158
Re: Red and Grey Hybridisation

Quote:
If red and grey ranges don't overlap, I'd be interested to know how the grey passes the parapoxy virus on to the reds.
You're right, I should've worded my response more carefully - sorry about that! Just to clarify, I should've said that their home ranges generally don't overlap significantly, even though the species' distributions might. The populations may be directly adjacent and there may well be some range overlap at the periphery, especially where mutually accessible food is prolific. Nonetheless, I think it's fair to say that for the most part, the two species typically do not intermingle. Assuming that's correct, and given that squirrels tend to focus most of their activity within their core territory, even where there are neighbouring populations of Greys and Reds, the two species probably don't come into direct contact -- and hence don't have the opportunity to mate -- with one another very often (if at all these days, thanks to human intervention). Hence it seems to me that this is a possible reason for the lack of hybridization.

However, as you rightly point out, the fact that the two probably don't bump into each other with any degree of regularity doesn't mean that the two species would never come into contact with each other, or -- more likely, in my opinion -- use the same feeding stations. Additionally, most populations have their share of itinerant individuals, which may pass through the territory/home range of individuals of both species - if one such individual were infectious, this provides opportunity for the virus to spread. Anyway, itinerants aside, Greys have been observed to pilfer Red caches (suggesting they do sometimes enter into Red territories) and, although I've not heard of any recently, there are reports of Red and Greys feeding together. So, with this in mind, it makes sense that one of the leading theories of squirrel poxvirus transmission is that the two species may come into contact with the same contaminated feeders. Given that the virus is very resistant to dessication, it seems logical that the virus could also be passed to other hard surfaces that the two might also come into contact with (e.g. branches where stripping or scent-marking has taken place, or pilfered caches) and this may play a role in its epidemiology. As you point out, there are other species (e.g. some ruminants) that can carry the virus and they may play a role in aiding the spread of the disease within and between populations.

Cheers,
Marc.
__________________
Marc Baldwin
My Website - Wildlife Online
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote
  #7 (permalink)  
Old 04-07-2009, 06:19 PM
Rob_D's Avatar
Member of the Wild Empire
 
Join Date: Mar 2008
Location: Baldock, Herts
Posts: 495
Blog Entries: 11
Re: Red and Grey Hybridisation

Even if they were capable of hybridising, sexual selection might stop it happening in nature. Possibly Red's just don't fancy grey's and vice-versa. If that were true, and there were suitable mates of their own species around, they would never try to hybridise. I suspect that squirrel mating is abit more consensual than with ducks?

They certainly have been recorded as being close together - some research papers mentioning that they had been found curled up together in dreys - though they were obviously just good friends
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote
  #8 (permalink)  
Old 04-07-2009, 07:18 PM
Gaina's Avatar
Commander of the Wild Empire
 
Join Date: Jun 2006
Location: Somerset, UK
Posts: 1,338
Blog Entries: 2
Re: Red and Grey Hybridisation

Quote:
Originally Posted by mbaldw View Post
You're right, I should've worded my response more carefully - sorry about that! Just to clarify, I should've said that their home ranges generally don't overlap significantly, even though the species' distributions might. The populations may be directly adjacent and there may well be some range overlap at the periphery, especially where mutually accessible food is prolific. Nonetheless, I think it's fair to say that for the most part, the two species typically do not intermingle. Assuming that's correct, and given that squirrels tend to focus most of their activity within their core territory, even where there are neighbouring populations of Greys and Reds, the two species probably don't come into direct contact -- and hence don't have the opportunity to mate -- with one another very often (if at all these days, thanks to human intervention). Hence it seems to me that this is a possible reason for the lack of hybridization.

However, as you rightly point out, the fact that the two probably don't bump into each other with any degree of regularity doesn't mean that the two species would never come into contact with each other, or -- more likely, in my opinion -- use the same feeding stations. Additionally, most populations have their share of itinerant individuals, which may pass through the territory/home range of individuals of both species - if one such individual were infectious, this provides opportunity for the virus to spread. Anyway, itinerants aside, Greys have been observed to pilfer Red caches (suggesting they do sometimes enter into Red territories) and, although I've not heard of any recently, there are reports of Red and Greys feeding together. So, with this in mind, it makes sense that one of the leading theories of squirrel poxvirus transmission is that the two species may come into contact with the same contaminated feeders. Given that the virus is very resistant to dessication, it seems logical that the virus could also be passed to other hard surfaces that the two might also come into contact with (e.g. branches where stripping or scent-marking has taken place, or pilfered caches) and this may play a role in its epidemiology. As you point out, there are other species (e.g. some ruminants) that can carry the virus and they may play a role in aiding the spread of the disease within and between populations.

Cheers,
Marc.
Thanks for the enlightenment, Marc .
__________________
Least favourite animal: Humans.
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote
  #9 (permalink)  
Old 04-07-2009, 07:38 PM
mbaldw's Avatar
Wild Member
 
Join Date: Jan 2006
Location: Southampton
Posts: 158
Re: Red and Grey Hybridisation

No worries, Gaina - it's about time I started making some sense today! I blame the heat I think RobD has the clincher here - even if Red and Grey did come into contact with each other, if no amount of wine, chocolates and flowers (or possibly mast and mating chases in this case!) ignite a 'spark' between them, then nothing's going to happen!

Cheers,
Marc.
__________________
Marc Baldwin
My Website - Wildlife Online
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote
  #10 (permalink)  
Old 04-07-2009, 08:03 PM
Gaina's Avatar
Commander of the Wild Empire
 
Join Date: Jun 2006
Location: Somerset, UK
Posts: 1,338
Blog Entries: 2
Re: Red and Grey Hybridisation

Quote:
Originally Posted by mbaldw View Post
No worries, Gaina - it's about time I started making some sense today! I blame the heat I think RobD has the clincher here - even if Red and Grey did come into contact with each other, if no amount of wine, chocolates and flowers (or possibly mast and mating chases in this case!) ignite a 'spark' between them, then nothing's going to happen!

Cheers,
Marc.
Hehe, a rodent bearing chocolates and flowers makes me think of Pepe Le Pew. And someone is now going to ruin the joke by telling me that Skunk belong to the Mephitidae family, not rodents - but I got there before ya! Ha!
__________________
Least favourite animal: Humans.
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote
  #11 (permalink)  
Old 04-07-2009, 10:07 PM
Rob_D's Avatar
Member of the Wild Empire
 
Join Date: Mar 2008
Location: Baldock, Herts
Posts: 495
Blog Entries: 11
Re: Red and Grey Hybridisation

Bugs Bunny was a hybrid Rabbit & Hare
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote
  #12 (permalink)  
Old 04-07-2009, 10:43 PM
volence's Avatar
Wild Member
 
Join Date: Jul 2008
Location: Birmingham
Posts: 239
Re: Red and Grey Hybridisation

If they did hybridise what do you reckon the result would look like?

Also bugs bunny was anthropomorphic so a hybridisation between a hare, a rabbit and a human! What was going through warner bros' minds?????
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote
  #13 (permalink)  
Old 04-07-2009, 07:34 PM
Paul mabbott's Avatar
Knight Commander of the Wild Empire
 
Join Date: Oct 2005
Location: Sheffield, FPRSY
Posts: 5,840
Re: Red and Grey Hybridisation

Quote:
Originally Posted by mbaldw View Post
.......... They certainly have the same number of chromosomes (2n = 40) and, although this is not the only necessary requisite, this does suggest that any hybrids could be fertile.
It's feasible that they might mate and produce offspring but there is surely no chance that the offspring could be fertile. Can anyone think of an example of a mammal (or indeed, vertebrate) where interspecific hybrids were fertile? The sort of thing that happens in plants but very rarely in animals ....
__________________
Ladybird Survey
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote
  #14 (permalink)  
Old 04-07-2009, 07:39 PM
Deer Stalker's Avatar
Commander of the Wild Empire
 
Join Date: Aug 2006
Location: Hampshire
Posts: 4,365
Blog Entries: 36
Re: Red and Grey Hybridisation

Quote:
Originally Posted by Paul mabbott View Post
Can anyone think of an example of a mammal (or indeed, vertebrate) where interspecific hybrids were fertile? The sort of thing that happens in plants but very rarely in animals ....
Red & Sika deer can hybridise & produce fertile offspring Paul.
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote
  #15 (permalink)  
Old 04-07-2009, 07:52 PM
mbaldw's Avatar
Wild Member
 
Join Date: Jan 2006
Location: Southampton
Posts: 158
Re: Red and Grey Hybridisation

Hi Paul,

Quote:
It's feasible that they might mate and produce offspring but there is surely no chance that the offspring could be fertile. Can anyone think of an example of a mammal (or indeed, vertebrate) where interspecific hybrids were fertile? The sort of thing that happens in plants but very rarely in animals ....
You're right that it's rare, but it's not unheard of. As Deer Stalker has mentioned, Red & Sika can produce fertile hybrids (both species have 64 to 68 chromosomes), as can several canids (e.g. coyotes, domestic dogs and wolves), some ungulates (the infamous 'Beefalo' is a fertile hybrid between American buffalo and a domestic cow), reptiles and some wallabies. As far as I am aware -- and I'm happy for someone to correct me here --, hybrid sterility is often (always?) the result of a mismatch in the number of chromosomes, which prevents the animal producing functioning gametes.

Cheers,
Marc.
__________________
Marc Baldwin
My Website - Wildlife Online
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote
Reply  

Bookmarks

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads

Thread Thread Starter Forum Replies Last Post
White / Grey Bee for Id please philipc Insects and Invertebrates 2 01-06-2009 10:02 PM
Grey Wagtail? whis4ey British Birds 8 04-06-2008 07:36 PM
law changes for Grey Squirrels JeffH Mammal Forums 68 02-04-2008 12:35 PM
Grey Herons rlchew British Birds 14 09-03-2008 07:30 PM
Not so grey really... WestLothian British Birds 5 20-05-2007 11:29 PM

» Log in

User Name:

Password:

Not a member yet?
Register Now!

» Online Users: 104

» New Wildlife Posts

Go to first new post Old...
Last post by SparklySarah
Today 12:59 AM
58 Replies, 392 Views
Go to first new post Red ribbon tied to...
Last post by SheffieldLass
Today 12:34 AM
39 Replies, 744 Views
Go to first new post Do you have a good...
Last post by Elean0r
Today 12:21 AM
54 Replies, 19,376 Views
Go to first new post Insect of the Day
Last post by Bruce Williams
Today 12:04 AM
819 Replies, 14,583 Views
Go to first new post id help please
Last post by stickman
Yesterday 11:54 PM
4 Replies, 69 Views
Go to first new post What Happened Here? - Koi
Last post by SparklySarah
Yesterday 11:53 PM
24 Replies, 261 Views
Go to first new post Owls of Bristol
Last post by Phoca Sibirica
Yesterday 11:33 PM
0 Replies, 16 Views
Go to first new post Nomada sp. Bee for ID
Last post by JRsbugs
Yesterday 11:16 PM
4 Replies, 55 Views

» New Environment Posts

Go to first new post Warm fusion = free clean...
Last post by Jim Ford
Today 12:16 AM
20 Replies, 129 Views
Go to first new post Why not real trees?
Last post by Rich_
Yesterday 09:55 PM
29 Replies, 632 Views
Go to first new post HHO Gas Cars
Last post by Jim Ford
Yesterday 04:41 PM
95 Replies, 9,112 Views
Go to first new post Global warming: Reasons...
Last post by Digit
Yesterday 11:01 AM
18 Replies, 873 Views

» New Activity Posts

Go to first new post Help needed with DSLR...
Last post by momji1971
Yesterday 09:46 PM
13 Replies, 150 Views
Go to first new post Coast to Coast Walk...
Last post by richnfamous
Yesterday 07:15 PM
70 Replies, 810 Views
Any good websites for...
Last post by Johnny Redgate
Yesterday 06:43 PM
16 Replies, 10,245 Views
Go to first new post Predator with prey images
Last post by gez
Yesterday 04:37 PM
14 Replies, 294 Views

» New Community Posts

Go to first new post adverts`
Last post by sunnydale
Yesterday 11:34 PM
16 Replies, 93 Views
Go to first new post Please sign palm oil...
Last post by loripo
Yesterday 09:29 PM
1 Replies, 39 Views
Go to first new post Question about the...
Last post by Jason Green
Yesterday 02:00 PM
60 Replies, 780 Views
Go to first new post Career change - blog
Last post by Dan Salter
Yesterday 01:08 PM
4 Replies, 150 Views

All times are GMT. The time now is 02:00 AM.


Copyright Wild About Britain 2009

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652